Trane Heating System SCWG 020 SCWG 025 SCWG 030 SCWG 035 SWG 020 SWG 025 SWG 030 SWG 035 SCRG 020 SCRG 025 SCRG 032 SRG 020 SCRG 025 SCRG 032 User Manual

Installation, Owner, and  
Diagnostic Manual  
IntelliPak®  
Commercial Self-Contained  
Modular Series, 20-35 Ton  
Models  
“BO” and later Design Sequence  
SCWG -020, -025, -030, -035  
SIWG -020, -025, -030, -035  
SCRG -020, -025, -032  
SIRG -020, -025, -032  
July 2000  
SCXG-SVX01B-EN  
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Contents  
Cross reference to related publications/information:  
IntelliPak® Self-Contained Programming Guide, PKG-SVP01B-EN  
Remote Air-Cool-Condenser Installation, Owner, and Diagnostic Manual, CXRC-  
SVX01A-EN  
2
Installation  
2
9
17  
33  
37  
39  
64  
74  
General Information  
Pre-installation Considerations  
Dimensions/Weights  
Mechanical Requirements  
Electrical Requirements  
Pre-Startup Requirements  
Programming  
Startup  
77  
Owner  
General Information  
Sequence of Operation  
Maintenance  
77  
91  
98  
Diagnostic Troubleshooting  
111  
111  
112  
Troubleshooting  
Diagnostics  
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General  
Information  
Installation  
Modular Series Self-Contained  
Unit Components  
cally or chemically cleanable.The  
evaporator fan is double width, double  
inlet and forward curved with a fixed  
pitch belt drive assembly. Frequency  
drives or inlet guide vanes are optional.  
Motor options are standard efficiency  
open drip proof (ODP) or totally enclosed  
fan cooled (TEFC); or premium efficiency  
ODP.  
condensing unit. Also, air-cooled units  
have two refrigerant circuits. Water-  
cooled units have four refrigerant circuits;  
which include a filter drier, pressure relief  
valve, liquid line service valve, sight glass/  
moisture indicator, thermal expansion  
valve with a sensing bulb and external  
equalizing line, discharge line shrader  
valve, a suction line shrader valve, and  
high and low pressure cutout switches.  
Water-cooled units also include a liquid  
line service valve for each circuit.  
Commercial self contained units are  
complete HVAC systems used in floor-by-  
floor applications. Units are easy to install  
because they feature a single point  
power connection, factory installed and  
tested controls, single water point  
connection, factory installed options, and  
an internally trapped drain connection.  
Modular self-contained units can ship as  
split-apart units for installation ease. Split-  
apart units ship with a dry nitrogen  
charge and require field refrigerant  
charging.  
All water-cooled units ship with a full  
refrigerant and oil charge. Air-cooled  
units ship with oil and a dry nitrogen  
holding charge and require field-piping  
refrigerant connections to the air cooled  
For more detailed information, see the  
Owners section of this manual.  
Units consist of multiple compressors,  
water-cooled condensers (water-cooled  
units only), an evaporator coil, dual  
forward curved fans, and control panel.  
Air-cooled units require a remote air-  
cooled condenser, model CXRC.The  
hermetically sealed 3-D scroll  
compressor motors utilize internal motor  
protection and time delays to prevent  
excessive cycling. Unit controls are either  
an electromechanical thermostat or  
microprocessor controls on the IntelliPak  
unit. See Figure I-GI-1 for a typical unit.  
The hermetically sealed 3-D scroll  
compressor motors utilize internal motor  
protection and time delays to prevent  
excessive cycling.  
The water-cooled condensers are shell  
and tube type with an internal subcooler.  
Condensers are available as mechani-  
Figure I-GI-1. IntelliPak® commercial self-contained Modular Series unit.  
4
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General  
Information  
Installation  
Control Options  
as unit control modules (UCM). In this  
manual, the acronym UCM refers to the  
entire control system network.  
Units can have either a thermostat  
control or IntelliPak® UCM control  
network.  
These modules perform specific unit  
functions using proportional/integral  
control algorithms. They are mounted in  
the unit control panel and are factory  
wired to their respective internal compo-  
nents. Each module receives and  
interprets information from other unit  
modules, sensors, remote panels, and  
customer binary contacts to satisfy the  
applicable request; i.e., economizing,  
mechanical cooling, heating, ventilation.  
See the Owners section of this manual  
for a detailed description of each  
IntelliPak® Unit Controls  
Standard controls supplied with the  
IntelliPak® unit include the human  
interface (HI) panel with unit control  
module (UCM), hi/lo inlet air temperature  
sensor, and frost protection. All setup  
parameters are preset from the factory.  
Human Interface Panel  
The HI is unit mounted and accessible  
without opening the units front panel. It  
allows easy setpoint adjustment using  
the HI keypad. In addition, the HI displays  
all unit operating parameters and  
conditions in a clear language display,  
which can be configured for either  
English, French, or Spanish.  
modules function.  
Optional Controls  
Optional controls include a disconnect  
switch, dirty filter switch, water flow  
switch (water-cooled only), supply air  
temperature reset, or external setpoint  
inputs. Night heat/morning warmup is  
available with electric, steam, or hot  
water heat control options.  
The optional remote human interface  
(RHI) will control up to four self-contained  
units, each containing an interprocessor  
communications bridge (IPCB). It has all  
the same features as the unit-mounted HI  
except for the service mode.  
The static pressure probe, zone night  
heat/morning warm up, supply air  
temperature reset sensor options ship  
separate inside the unit control panel for  
field installation. For more detailed  
information on the unit control options,  
see the Owners section of this manual.  
For more information on setpoint defaults  
and ranges and unit programming, see  
the IntelliPak® Self-Contained Program-  
ming Guide, PKG-SVP01B-EN. A copy  
ships with each unit.  
Unit Control Module  
Unit Nameplate  
The UCM provides smartunit control  
with safety features and control relays  
for pumps, dampers, etc. The Modular  
Series IntelliPak® self-contained unit is  
controlled by a microelectronic control  
system that consists of a network of  
modules.These modules are referred to  
The unit nameplate identifies the unit  
model number, appropriate service  
literature, and wiring diagram numbers. It  
is mounted on the left end of the unit  
control panel.  
SCXG-SVX01B-EN  
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General  
Information  
Installation  
Model Number Description  
Each self-contained unit has a multiple character model number unique to that unit.To determine a units specific options, reference  
the model number on the unit nameplate using the model number explanation below.  
S C W G N 20 4 2 BO A B 2 10  
065  
B
A 1 0 1 0 A A C F A 1 1 0 T 2 0  
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36  
Digit 1 - Unit Model  
C = Horizontal Discharge  
D = Horizontal Discharge w/ Double  
Wall  
115 = 1150 rpm  
120 = 1200 rpm  
125 = 1250 rpm  
130 = 1300 rpm  
135 = 1350 rpm  
140 = 1400 rpm  
145 = 1450 rpm  
150 = 1500 rpm  
155 = 1550 rpm  
160 = 1600 rpm  
165 = 1650 rpm  
170 = 1700 rpm  
175 = 1750 rpm  
180 = 1800 rpm  
185 = 1850 rpm  
S = Self Contained  
Digit 2 - UnitType  
E
F
= Vertical Discharge, Ship Separate  
= Vertical Discharge w/ DoubleWall,  
Ship Separate  
C = Commercial  
I
= Industrial  
Digit 3 - Condenser Medium  
W = Water-Cooled  
R = Remote Air-Cooled  
G = Horizontal Discharge, Ship Separate  
H = Horizontal Discharge w/ Double  
Wall, Ship Separate  
Digit 4 - Development Sequence  
G = Modular Series  
Digit 13 - PlenumType  
B = Std Plenum w/ Factory Cut Holes  
C = Low Plenum w/ Factory Cut Holes  
Digit 5 - Refrigerant Circuit Configuration  
N = Independent  
E
F
= Std Plenum w/ Field Cut Holes  
= Low Plenum w/ Field Cut Holes  
Digit 6, 7 - Unit Nominal Capacity  
20 = 20Tons (Water or Air Cooled)  
25 = 25Tons (Water or Air Cooled)  
30 = 30Tons (Water Cooled Only)  
32 = 32Tons (Air Cooled Only)  
35 = 35Tons (Water Cooled Only)  
H = Std Plenum DoubleWall (Perf)  
w/ Field Cut Holes  
J
Digit 20 - HeatingType  
A = Steam Coil, LH  
B = HotWater Coil, LH  
C = Electric Heat, 1 Stage  
= Low Plenum DoubleWall (Perf)  
w/ Field Cut Holes  
= Std. Plenum w/Factory Cut Holes,  
Ship Separate  
L
F
= Hydronic Heat Ctrl Interface  
Digit 8 - UnitVoltage  
M = Low Plenum with Factory Cut  
Holes, Ship Separate  
G = Elec. Heat Ctrl Interface, 1 stage  
K = Steam Coil Ship Separate, LH  
6
4
5
= 200Volt/60 Hz/3 ph  
= 460Volt/60 Hz/3 ph  
= 575Volt/60 Hz/3 ph  
P
= Std Plenum w/ Field Cut Holes, Ship  
Separate  
L
= Hot Water Coil Ship Separate, LH  
M = Steam Coil, RH  
R = Low Plenum w/ Field Cut Holes,  
Ship Separate  
N = HotWater Coil, RH  
Digit 9 -AirVolume/Temp Control  
P
= Steam Coil Ship Separate, RH  
1
2
3
4
5
6
= I-Pak & IGV and Supply AirTemp  
Ctrl  
= I-Pak &VFD and Supply Air  
Temp Ctrl  
= I-Pak &VFD w/ Bypass and  
Supply AirTemp Ctrl  
= I-Pak w/oVol. CTRL, w/ ZoneTemp  
Cool  
= I-Pak w/oVol. CTRL, w/ ZoneTemp  
Heat/Cool  
U = Std Plenum DoubleWall (Perf) w/  
Field Cut Holes, Ship Separate  
V = Low Plenum DoubleWall (Perf) w/  
Field Cut Holes, Ship Separate  
R = HotWater Coil Ship Separate, RH  
= None  
0
Digit 21 - Unit Isolators  
A = Isopads  
0
= Without Plenum  
B = Spring Isolators  
Digit 14 - MotorType  
0
= None  
1
2
3
= Std. Efficiency ODP  
Digit 22 - Unit Finish  
= Premium Eff. ODP  
1
2
3
= Paint - Executive Beige  
= Protective Coating  
= Protective Coating w/ Finish Coat  
= Std. EfficiencyTotally Enclosed  
= I-Pak w/oVol. CTRL, w/ Supply Air  
Temp Ctrl  
Digit 15, 16 - Motor HP  
05 = 5 HP Motor  
07 = 7.5 HP Motor  
10 = 10 HP Motor  
15 = 15 HP Motor  
20 = 20 HP Motor  
25 = 25 HP Motor  
Digit 23  
8
9
= Thermostat Interface  
= Thermostat Interface w/Anti-Short  
CycleTimer  
0
= None  
Digit 24 - Unit Connection  
A = Thermostat Interface w/  
Compressor Start Delay  
B = Thermostat Interface w/Anti-Short  
CycleTimer and Comp. Start Delay  
1
2
3
= Disconnect Switch  
= Terminal Block  
= Dual Point Power  
Digit 17, 18, 19 - Fan RPM  
085 = 850 rpm  
090 = 900 rpm  
095 = 950 rpm  
Digit 25 - Industrial Options  
A = Protective Coated Evaporator Coil  
B = Silver Solder  
Digit 10, 11 - Design Sequence  
BO = BDesign  
C = Stainless Steel Screws  
D = A and B  
Digit 12 - Unit Construction  
A = Vertical Discharge  
B = Vertical Discharge with DoubleWall  
100  
105  
110  
=
=
=
1000 rpm  
1050 rpm  
1100 rpm  
E
= A and C  
6
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General  
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Installation  
F = B and C  
G = A, B and C  
0 = None  
H = Ventilation For 2 Pos. Cntrl Interface  
0 = None  
Digit 33 - Control Interface Options  
A = Generic BAS Module (GBAS)  
B =Ventilation Override Module (VOM)  
C =Tracer Comm. Interface Module (TCI)  
D= Remote Human Interface (RHI)  
E= GBAS and TCI  
Digit 29 - Water Piping  
Digit 26 - Drain PanType  
A = Galvanized Sloped  
B = Stainless Steel Sloped  
A = Right Hand Condenser Connection  
B = Left Hand Condenser Connection  
C = Right Hand Basic Piping  
D = Left Hand Basic Piping  
E = Right Hand Intermediate Piping  
F = Left Hand Intermediate Piping  
J = Right Hand Basic w/ Flow Switch  
K = Left Hand Basic w/ Flow Switch  
L = Right Hand Intermediate  
w/ Flow Switch  
F= VOM and TCI  
Digit 27 - Waterside Economizer  
A = Mechanical Clean Full Cap. (4-row)  
B = Mechanical Clean Low Cap. (2-row)  
C = Chemical Clean Full Cap. (4-row)  
D = Chemical Clean Low Cap. (2-row)  
E = Mechanical Clean Full Capacity  
(4-row) Ship Separate  
F = Mechanical Clean Low Capacity  
(2-row) Ship Separate  
G = Chemical Clean Full Capacity  
(4-row) Ship Separate  
G = GBAS and VOM  
H = GBAS and RHI  
J = VOM and RHI  
K = TCI and RHI  
L = GBAS, VOM, and TCI  
M = GBAS, VOM, and RHI  
N = GBAS, TCI, and RHI  
P = VOM, TCI, and RHI  
M = Left Hand Intermediate  
w/ Flow Switch  
0 = None  
R = GBAS, VOM, TCI, and RHI  
0 = None  
Digit 30 - Condenser Tube Type  
A = Standard Condenser Tubes  
B = 90/10 CuNi CondenserTubes  
0 = None  
Digit 34 - Agency  
T = UL Agency Listing  
0 = None  
H = Chemical Clean Low Capacity  
(2-row) Ship Separate  
0 = None  
Digit 35 - FilterType  
1 = 2-inch Construction Throwaway  
2 = 2-inch Med Eff. Throwaway  
Digit 28 -Ventilation Control  
B = Airside Econ w/TraqDamper  
(Top O/A Inlet)  
Digit 31 - Compressor Service Valves  
1 = With Service Valves  
0 = None  
C = Airside Econ w/ Standard  
Dampers (Top O/A Inlet)  
Digit 36 - Miscellaneous Control Option  
A = Low Entering AirTemp. Protect  
Device (LEATPD)  
Digit 32 - Miscellaneous System Control  
1 = Timeclock  
E = Airside Econ w/TraqDamper and  
Comparative Enthalpy  
2 = Interface for Remote HI  
3 = Dirty Filter Switch  
4 = 1 and 2  
B = High Duct Temp T-Stat  
C = Plenum High Static Switch  
D = Kit for Heat Mode Output (w/tstat)  
E = A and B  
(Top O/A Inlet)  
F = Airside Econ w/ Std Dampers and  
Comparative Enthalpy (Top O/A  
Inlet)  
5 = 1 and 3  
6 = 2 and 3  
F = A and C  
7 = 1, 2, and 3  
G = Traq Damper Ventilation Interface  
G = B and C  
0 = None  
H = A, B, and C  
0 = None  
Self-Contained Ship-With Accessory Model Number Description  
P
1
S
2
W
3
G
4
S
5
A
6
1
7
1
8
0
9
AO  
10 11  
P = BAYSTAT037A - 2 Heat/2 Cool  
Programmable Thermostat  
0 = None  
Digit 1 - Parts/Accessories  
C = BAYSENS014 - ZoneTemp with  
P = Parts/Accessories  
Timed Override Button, Setpoint Dial  
(CV andVAV)  
Digit 2 - Unit Model  
S= Self-Contained  
D = BAYSENS023 - Remote Min. Position  
Potentiometer Control (OA Damper)  
E = BAYSENS008 - CV Zone Sensor  
F = BAYSENS010 - CV Zone Sensor with  
Indicator Lights  
G = BAYSENS019 - CV Programmable  
Night Setback Sensor  
H = BAYSENS021 - VAV Zone Sensor  
with Indicator Lights  
J = BAYSENS020 - VAV Programmable  
Night Setback Sensor  
K = Remote Sensor Kit  
Digit 7 - Mixed Air Temperature Protec-  
tion Kit (field installed)  
1 = Mixed AirTemperature Protection Kit  
0 = None  
Digit 3 - Shipment  
W = With Unit  
Digit 4 - Development Sequence  
F = Signature Series  
G = Modular Series  
Digit 8 - Carbon Dioxide Sensor (field  
installed)  
1 = Carbon Dioxide Sensor Kit  
0 = None  
Digit 5 - Sensors and Other Accessories  
S = Sensors  
Digit 9 - Future Option  
0 = None  
Digit 6 - Sensors and Thermostats (field  
installed)  
A = BAYSENS017 - ZoneTemp Only (C V  
andVAV)  
B = BAYSENS013 - ZoneTemp with  
Timed Override Button (CV andVAV)  
Digit 10, 11 - Design Sequence  
A0 = A Design  
L = Outside AirTemperature Sensor Kit  
M = Outside Air Humidity Sensor Kit  
N = BAYSTAT010 - 2 Heat/2 Cool  
Thermostat  
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General  
Information  
Installation  
After-ShipmentAccessory Model Number  
S C W F N 20 4 2 AO A B 2 10  
065  
B
A 1 0 1 0 A A C F A 1 1 0 T 2 0  
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36  
Digit 1 - Parts/Accessories  
10 = 10 HP Motor  
J = BAYSENS020 -VAV Programmable  
Night Setback Sensor  
P = Parts/Accessories  
15 = 15 HP Motor  
20 = 20 HP Motor  
K = Remote Sensor Kit  
Digit 2 - Unit Model  
S= Self-Contained  
25 = 25 HP Motor  
L = Outside AirTemperature Sensor Kit  
M = Outside Air Humidity Sensor Kit  
0 = None  
30 = 30 HP Motor  
Digit 3 - Shipment  
A = After Unit  
40 = 40 HP Motor  
50 = 50 HP Motor (460V & 575V Only)  
0 = Not Defined  
Digit 22 - Low Entering Air Temperature  
Protection Device  
1 = Low Entering AirTemperature  
Protection Device Kit  
0 = None  
Digit 4 - Development Sequence  
F = Signature Series  
G = Modular Series  
Digit 15 - Exhaust/Comparative Enthalpy  
Module (Field Installed)  
1 = ECEM Kit  
Digit 5 - Condenser Medium  
W = Water Cooled  
R = Remote Air Cooled  
2 = None  
Digit 23 - High Duct Temperature  
Thermostat  
1 = High DuctTemp.Thermostat Kit  
0 = None  
Digit 16 - Generic BAS Module  
1 = GBAS 0-5 VDC Kit  
0 = None  
Digit 6 - Refrigerant Circuit Configuration  
N = Independent (Water-Cooled)  
M = Manifolded (Air-Cooled)  
Digit 17 - Heat Module  
1 = Electric Heat Module Kit  
2 = Hydronic Heat Module Kit  
0 = None  
Digit 24 - Plenum High Static Switch  
1 = Plenum High Static Switch Kit  
0 = None  
Digits 7, 8 - Unit Nominal Capacity  
20 = 20Tons (Water or Air)  
22 = 22Tons (Water Only)  
25 = 25Tons (Water or Air)  
29 = 29Tons (Water or Air)  
30 = 30Tons (Air Only)  
32 = 32Tons (Water Only)  
35 = 35Tons (Water or Air)  
38 = 38Tons (Water Only)  
40 = 40Tons (Air Only)  
42 = 42Tons (Water Only)  
46 = 46Tons (Water Only)  
50 = 50Tons (Air Only)  
52 = 52Tons (Water Only)  
58 = 58Tons (Water Only)  
60 = 60Tons (Air Only)  
Digits 25 45 - Future Use  
0 = None  
Digit 18 - Remote Human Interface and  
IPCB  
1 = Remote Human Interface Panel Kit  
(RHI Only)  
2 = Interprocessor Communications  
Module Kit (IPCB Only)  
3 = RHI and IPCB Kit  
0 = None  
Digit 19 -Tracer Communications  
Interface Kit (TCI)  
1 = TCI Comm 3 Kit  
0 = None  
65 = 65Tons (Water Only)  
72 = 72Tons (Water Only)  
80 = 80Tons (Water Only)  
Digit 20 -Ventilation Override Module Kit  
(VOM)  
1 = VOM Kit  
0 = None  
Digit 9 - UnitVoltage  
6 = 200Volt/60 Hz/3 ph  
4 = 460Volt/60 Hz/3 ph  
5 = 575Volt/60 Hz/3 ph  
0 = Not Defined  
Digit 21 - Sensors and Thermostats  
A = BAYSENS017 - ZoneTemp Only (CV  
andVAV)  
B = BAYSENS013 - ZoneTemp with  
Timed Override Button (CV andVAV)  
C = BAYSENS014 - ZoneTemp with  
Timed Override Button, Setpoint Dial  
(CV andVAV)  
Digits 10, 11 - Design Sequence  
A0 = A Design  
Digit 12 - Unit Power Connection  
1 = Single Point Power  
2 = Dual Point Power  
E = BAYSENS008 - CV Zone Sensor  
F = BAYSENS010 - CV Zone Sensor with  
Indicator Lights  
0 = Not Defined  
G = BAYSENS019 - CV Programmable  
Night Setback Sensor  
H = BAYSENS021 -VAV Zone Sensor  
with Indicator Lights  
Digit 13, 14 - Motor HP  
05 = 5 HP Motor  
07 = 7.5 HP Motor  
8
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Pre-Installation  
Considerations  
Installation  
Receiving and Handling  
o Do not move damaged material from  
the receiving location. It is the receivers  
responsibility to provide reasonable  
evidence that concealed damage did  
not occur after delivery.  
o Notify the carriers terminal of the  
damage immediately by phone and  
mail. Request an immediate joint  
inspection of the damage by the carrier  
and consignee.  
Shipping Package  
Commercial self-contained units ship  
assembled on skids with protective  
coverings over the coil and discharge  
openings. Figure I-PC-1 illustrates a  
typical shipping package.  
o Do not continue unpacking the  
shipment if it appears damaged. Retain  
all internal packing, cartons, and crate.  
Take photos of damaged material if  
possible.  
o Notify yourTrane representative of  
the damage and arrange for repair.  
Have the carrier inspect the damage  
before making any repairs to the unit.  
Ship-Separate Accessories  
Field-installed sensors ship separately  
inside the units main control panel. Extra  
filters, sheaves, and belts ship in the units  
fan motor section. Condenser plugs,  
spring isolators, and isopads ship in the  
units bottom left side.  
Receiving Checklist  
Complete the following checklist  
immediately after receiving unit  
shipment to detect possible shipping  
damage.  
o Inspect individual cartons before  
accepting. Check for rattles, bent carton  
corners, or other visible indications of  
shipping damage.  
o If a unit appears damaged, inspect it  
immediately before accepting the  
shipment. Make specific notations  
concerning the damage on the freight  
bill. Do not refuse delivery.  
o Inspect the unit for concealed  
damage before it is stored and as  
soon as possible after delivery.  
Report concealed damage to the  
freight line within the allotted time  
after delivery. Check with the  
carrier for their allotted time to  
submit a claim.  
Figure I-PC-1. Typical unit mounted on shipping skid.  
SCXG-SVX01B-EN  
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Pre-Installation  
Considerations  
Installation  
Installation Preparation  
Before installing the unit, perform  
the following procedures to  
ensure proper unit operation.  
5. Remove the protective shipping covers  
from the unit. Refer to the Unit  
Protective Coverssection on page 39.  
Note: Unit height and connection locations  
will change if external vibration isolators  
are used. The unit may be raised an  
1.Verify the floor or foundation is level.  
Shim or repair as necessary.To ensure  
proper unit operation, install the unit  
level (zero tolerance) in both horizontal  
axis. Failure to level the unit properly  
can result in condensate management  
problems, such as standing water  
inside the unit. Standing water and wet  
surfaces inside units can result in  
microbial growth (mold) in the drain  
pan that may cause unpleasant odors  
and serious health-related indoor air  
quality problem.  
7
additional 5 /8 inches with spring-type  
isolators.  
Note: Unit height and connection locations  
will change if the unit is constructed to be  
split-a-part in the field. See unit submittal  
drawings for connection locations.  
6. Electrical supply power must meet  
specific balance and voltage  
requirements, as described in the  
Electrical Requirementssection on  
page 37.  
2. Allow minimum recommended  
clearances for maintenance and  
routine service. See Service Access”  
section on page 11.  
7. Water-cooled units only (model  
SXWG): The installer must furnish and  
install a condenser main and standby  
water pump, cooling tower, pressure  
gauges and all components for the  
waterside piping. See the Water  
Pipingsection on page 34 for general  
waterside recommendations.  
3. Position the unit and skid assembly in  
its final location. If unit shipped split-  
apart, follow the procedure in the  
Split-Apart Unit Assemblysection  
on page 14 before completing this  
step.Test lift the unit to determine  
exact unit balance and stability before  
hoisting it to the installation location.  
See Figure I-PC-7 and I-PC-8 on page  
13 for typical rigging procedures,  
including cautions and proper uses of  
such equipment as fork lifts, spreader  
bars, and hooks.  
8. Air-cooled units only (model SXRG):  
These units require field-installation of a  
remote air-cooled condenser and  
refrigerant piping. See the Refrigerant  
Pipingsection on page 36 for general  
piping recommendations.  
4. Remove the skids from under the unit.  
See the Rigging and Handling”  
section on page 12. Refer to the Skid  
Removalsection on page 16. If you  
find internal damage, file a claim  
immediately to the delivering carrier.  
10  
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Pre-Installation  
Considerations  
Installation  
Service Access  
denser and fan motor access panels are  
secured with quick-acting fasteners.  
Access panels for evaporator coils,  
expansion and water valves, and left fan  
bearing are sheet metal screws. Access  
to other components for service requires  
removal of panels secured with sheet  
metal screws. During operation, sight  
glasses are viewable through portholes  
on the upper right side panel of the fan  
section.  
See Figure I-PC-4 andTable I-PC-1 for  
recommended service and code  
clearances. Access to thermostat unit  
controls is through a hinged access panel  
door on the front, lower left of the units  
compressor section.  
IntelliPak® unit control access is through a  
panel on the middle right of the fan  
section. The panel is secured with an  
automatic latch and quick-acting fasten-  
ers, which require a screwdriver to open.  
ƽ WARNING  
!
Removable front unit panels provide  
access to compressors, fan, motor, inlet  
guide-vane actuator, and belts.  
Disconnect electrical power  
source before servicing the unit.  
Failure to do so may result in  
injury or death from electrical  
shock or entanglement in moving  
parts.  
Removable left side panels give access to  
drive side, fan bearing, inlet guide-vanes,  
condensers, and waterside economizer  
control valve.The compressor, con-  
Table I-PC-1. SCWG/SIWG/SCRG/SIRG Clearance Requirements  
Side  
Distance  
Purpose  
Front  
Left  
42 in. (1066 mm)  
18 in.  
NEC code requirement  
Air-cooled units only  
36 in. (914 mm)  
77 in.  
Refrigeration and waterside component service  
Fan shaft removal  
Provides uniform airflow  
Provides uniform airflow  
Right  
Inlet  
36 in. (914 mm)  
18 in. (457 mm)  
18(457.2 mm)  
Minimum  
Air Inlet  
36(914 mm)  
Minimum  
SeeTable  
42(1066.8 mm)  
Minimum  
Figure I-PC-4. Top view of self-contained unit showing recommended service and code  
clearances.  
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Pre-Installation  
Considerations  
Installation  
Rigging and Unit Handling  
Before lifting the unit or modular  
component, determine the approximate  
center of gravity for lifting safety. See  
Figure I-PC-5 for assembled modular  
units and Figure I -PC-6 for split-apart  
units. The center of gravity may vary  
slightly within the gravity block  
depending on unit options.  
WARNING  
!
Ensure lifting equipment capacit
exceeds unit weight by an  
adequate safety factor to prevent  
injury, death, or unit damage.  
Always test-lift the unit to determine the  
exact unit balance and stability before  
hoisting it to the installation location. See  
Figures I-PC-7 and I-PC-8 for typical  
rigging procedures and proper rigging  
equipment usage.  
Figure I-PC-5. Assembled unit gravity block location.  
Table I-PC-2. Gravity Block Dimensions  
ƽ WARNING  
!
Model  
A
B
C
D
SXWG  
36  
14  
38  
12  
To prevent injury or death and  
unit damage, always test-lift the  
unit to determine actual center of  
gravity. See Figures I-PC-5 and I-  
PC-6.  
SXRG  
36  
16  
40  
12  
Fan Section Only  
Compressor Section Only  
12  
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Pre-Installation  
Considerations  
Installation  
Rigging and Handling  
Unit Shipping  
1. Position rigging sling under wood  
shipping skid.  
2. Use spreader bars to avoid unit  
damage.  
3. When using a forklift, exercise caution  
to prevent unit damage.  
4. Use the standard fork length to lift one  
end and drag or pull unit while skidding  
the opposite end.  
5. The unit center of gravity will fall within  
center of gravity block at various  
locations depending on unit options.  
6. Use hooks to lift fan section only. Do not  
hook into open channels to lift unit.  
7. See unit nameplate for unit weight.  
8. Do not stack units.  
ƽ CAUTION  
!
Do not use hooks to lift unit or  
hook into open channels to lift  
unit. This could cause unit  
damage.  
Figure I-PC-7. Assembled modular unit proper rigging.  
Fan Section  
Figure I-PC-8. Split-apart modular unit proper rigging.  
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Pre-Installation  
Considerations  
Installation  
Split-Apart Unit Assembly  
1. Ensure the tagging information on the  
fan section nameplate matches that on  
the compressor nameplate.  
2. Remove the connector brackets holding  
the the sheet metal shipping cover on  
compressor section. Retain brackets  
and screws.  
3. Remove shipping cover from the  
compressor section and verify the ship-  
with packge contains:  
13. Remove panel FLR and open the  
bottom control panel door, FLL. Pull the  
fan motor leads (coiled in the fan  
section) through the knockout in the  
bottom of the fan section to the control  
panel. Ensure that the bushing is  
installed in the hole to prevent the  
wires from chafing. Refer to the unit  
wiring diagrams to connect the fan  
motor leads properly and ensure  
correct phase sequencing.  
suction and discharge line couplings  
insulation  
IntelliPak Units (UCM) Only  
sheet metal screws  
14. Remove panels FML, FMM, and FMR.  
15. Pull the circular plug connector (CPC)  
from the compressor section through  
the knockouts into the fan section.  
Install the bushings (provided on the  
wiring harnesses) in the knockouts.  
16. Using the CPC wiring diagram,  
connect the male CPC to the female  
CPC in the top control panel.  
4. Lift fan section onto the compressor  
section using the rigging method in  
Figure I-PC-8 on page 13.  
5. Remove skid from the fan section,  
placing the fan section onto the  
compressor section. Reference Figure I-  
PC-9 on page 15.  
6. Install the connection brackets with the  
sheet metal screws (referenced in step  
2) on all sides of the unit. Reference  
Detail Ain Figure I-PC-9.  
17. If the unit has the mixed air  
temperature option, route the capillary  
tube on back of the filter rack.  
7. Remove the unit panels labeled RU and  
RL in Figure I-PC-10 on page 15.To  
remove panels, first remove the four  
shipping screws located in the corner of  
each panel. Next, turn the remaining 1/4  
turn fasteners to the unlatch position.  
The panel is supported by a lip”  
channel. So, lift the panel up and off the  
unit to remove it. See Detail Ain Figure  
I-PC-9 on page 15.  
Units withThermostat Only  
18. Remove panel FMR. See Note 1 on  
Figure I-PC-10.  
19. Pull frost protection wires from the  
bottom control panel throughknockouts  
in bottom of fan section. Route wires to  
the appropriate frost protection  
switches on the evaporator coil.  
Reference the unit wiring diagrams to  
connect frost protection wiring  
connectors.  
8. Connect the drain hose to the drainpan  
outlet fitting and secure it with the drain  
hose clamp provided.  
9. Circulate nitrogen thoughout  
refrigerant circuits.  
10. Unbraze and remove the caps on the  
discharge and suction lines in both the  
compressor and fan sections.  
11. Install and braze discharge and suction  
line couplings.  
12. Insulate discharge and suction lines  
with the insulation provided.  
Air-Cooled Units Only:  
20. Route the refrigerant circuit wires for  
circuits 1 and 2 from the bottom control  
panel through the knockouts to the  
solenoid valves.The solenoid valves  
are located in the liquid refrigerant  
lines on the right-hand side of the unit.  
Refer to the unit wiring diagrams to  
make splice connections.  
14  
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Considerations  
Installation  
Figure I-PC-9 How to assemble the split apart modular unit.  
Figure I-PC-10 Modular unit panel description and internal connections.  
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Pre-Installation  
Considerations  
Installation  
Skid Removal  
The unit ships on skids to provide forklift  
locations from the front or rear.The skid  
allows easy maneuverability of the unit  
during storage and transportation.  
Remove the skids before placing the unit  
in its permanent location.  
Remove the skids using a forklift or jack.  
Lift one end of the unit off of the skids.  
See Figure I-PC-5 and I-PC-6 on page 12  
for unit gravity block location. Slide the  
skids out and lower the unit at the  
installation location.  
Note: External isolation is not necessary  
since units are internally isolated. Consult a  
vibration specialist before “double-  
isolating” the unit.  
Figure I-PC-9. Optional spring isolator dimensional data.  
External Unit Isolation  
the unit off the isolator and turn the  
leveling bolt counterclockwise. Recheck  
the unit level and the housing  
clearances. Maximum allowable  
difference between isolator heights is 1/4  
inch. Shim as required under the  
isolators.  
conditioned supply air discharges  
through the top.  
If your job requires external vibration  
isolation, two options are available:  
isopads or spring-type isolators. Isopads  
should be placed under the unit at  
locations indicated on the factory-  
provided isolator sheet.  
o Electrical connection knockouts are on  
the top, left side of the unit.  
o Allow adequate space for piping  
access and panel removal. Condenser  
water piping, refrigerant piping, and  
condensate drain connections are on  
the lower left end panel.  
Set the spring-type isolators (Figure I-PC-  
9) in position after the unit is removed  
from skids before making electrical,  
piping, or duct connections. All units  
require a minimum of four isolators per  
unit. But some may require six isolators,  
depending upon unit options. Note: The  
Trane Company strongly recommends  
you consult a vibration specialist before  
double-isolating the unit. Double isolation  
is not recommended.  
Note: The compressors and fan assembly  
are internally isolated on most units. Due  
to this, the addition of external isolation  
devices (spring mounting isolators) is at  
the discretion of the building or HVAC  
system designer.  
Note: Unit height and connection locations  
will change if using vibration isolators. The  
unit height may increase up to 5 7/8” with  
spring type isolators.  
Pre-Installation Checklist  
Complete the following checklist before  
beginning unit installation.  
If you decide to externally isolate the unit,  
use spring-flex, type CP isolators. The  
spring number is marked on the outer  
housing. See Figure I-PC-9.  
o Electrical supply power must meet  
specific balance and voltage  
requirements as described in the  
Electrical Requirementssection on  
page 37.  
o Verify the unit size and tagging with the  
unit nameplate.  
o Make certain the floor or foundation is  
level, solid, and sufficient to support the  
unit and accessory weights. SeeTable  
I-DW-1 on page 32. Level or repair the  
floor before positioning the unit if  
necessary.  
To install external isolators, complete the  
following procedure.  
1. Locate the isolators under unit base at  
the locations indicated on the factory-  
provided isolator placement sheet. Lift  
one end of the unit at a time to position  
isolators to the floor, using anchor bolts.  
o Water-cooled units only: The installer  
is responsible for providing a condenser  
main, standby water pump, cooling  
tower, pressure gauges, strainers, and  
all components for waterside piping.  
See the Water Pipingsection on page  
34 for general waterside  
o Allow minimum recommended  
clearances for routine maintenance and  
service. Refer to unit submittals for  
dimensions.  
2. Level the unit by adjusting isolator  
heights. Unit weight may cause the  
upper housing to rest on the lower  
housing of the spring isolators. The  
isolator clearance shown in the side  
view of Figure I-PC-9, must be 1/4 - 1/2  
inches.To increase the clearance, lift  
recommendations.  
o Air-cooled units only: The installer is  
responsible for providing and installing  
the remote air-cooled condenser and  
refrigerant piping, including filter driers.  
o Allow three fan diameters above the  
unit for the discharge ductwork. Return  
air enters the rear of the unit and  
16  
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Dimensions  
and Weights  
Installation  
SCWG/SIWG Unit —  
English - (inches)  
ON PAGE 21  
ON PAGE 20  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
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Dimensions  
and Weights  
Installation  
SCWG/SIWG Unit —  
Metric- (mm)  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
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Dimensions  
and Weights  
Installation  
SCRG/SIRG Unit —  
English - (inches)  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
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Dimensions  
and Weights  
Installation  
SCRG/SIRG Unit —  
Metric - (mm)  
ON PAGE 21  
ON PAGE 21  
ON PAGE 21  
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Dimensions  
and Weights  
Installation  
SCRG/SIRG/SCWG/SIWG Detail  
AElectrical Connections —  
English - (inches)  
SCRG/SIRG/SCWG/SIWG Detail  
AElectrical Connections —  
Metric - (mm)  
Detail BDischarge Options English - (inches) and Metric (mm)  
Unit Dimensions - English, (inches)  
UnitTons  
A
20  
B
C
D
E
F
3
1
1
1
1
SCWG/SCRG 20  
SCWG/SCRG 25  
SCWG 30 - 35/SCRG 32  
10 /4 58 /2 5 /8  
13 /4 11 /2  
19 1/4 12 1/4 57 5/8 5 1/8  
13 1/4 11 /2  
1
1
18  
14 5/8 56 1/2 5 1/8  
13 1/4 11 /2  
Unit Dimensions - Metric (mm)  
UnitTons  
A
B
C
D
E
F
SCWG/SCRG 20  
SCWG/SCRG 25  
SCWG 30 - 35/SCRG 32  
508  
489  
457  
508  
489  
457  
1486 130  
1464 130  
1435 130  
337  
337  
337  
292  
292  
292  
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Dimensions  
and Weights  
Installation  
Hot Water Coil  
Hot Water Coil Dimensions - English - (inches)  
UnitTon  
20 - 35  
A
B
C
D
E
F
G
H
J
7 /4  
1
3
5
1
7
1
1
5
3
37 /4 53 /4 16 /8 73 /2 14 /8 16 /4 43 /4 5 /8  
Hot Water Coil Dimensions - Metric (mm)  
UnitTon  
20 - 35  
A
946  
B
C
D
E
F
413  
G
H
J
187  
1365 422  
1867 378  
1099 143  
22  
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Dimensions  
and Weights  
Installation  
Steam Coil  
Steam Coil Dimensions - English - (inches)  
UnitTon  
20 - 35  
A
B
C
D
E
K
L
M
15 7/8  
N
1
P
41  
Q
9 3/8  
R
4 3/8  
37 1/4 53 3/4 16 5/8 73 1/2 10 7/8 22 1/2 3 3/8  
Steam Coil Dimensions - Metric (mm)  
UnitTon  
20 - 35  
A
946  
B
C
D
E
K
572  
L
86  
M
403  
N
25  
P
Q
R
111  
1365 422  
1867 276  
1041 238  
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Dimensions  
and Weights  
Installation  
Electric Heat Coil  
24  
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Dimensions  
and Weights  
Installation  
Waterside Economizer  
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Dimensions  
and Weights  
Installation  
Airside Economizer Dimensions - English - (inches)  
Unit Size  
SCWG/SIWG 20, 25  
A
36  
B
C
D
E
F (1)  
F (2)  
G (1) G (2) H (1) H (2)  
J
K
L
M
49 3/4  
65 5/8 37  
74 1/4 6 1/8  
56 1/2 49 3/4 23 1/4 20 1/2 5 5/8  
7
20 1/2 17 1/8 17  
SCRG/SIRG 20  
SCWG/SIWG 30, 35  
SCRG/SIRG 25, 32  
36  
65 5/8 37  
74 1/4 6 1/8  
61 3/8 62 3/4 28 1/8 20 1/2 3 1/4  
7
20 1/2 17 1/8 5 1/2  
62 3/4  
Airside Economizer Dimensions - Metric (mm)  
Unit Size  
A
B
C
D
E
F (1)  
F (2)  
G (1) G (2) H (1) H (2)  
J
K
L
M
SCWG/SIWG 20, 25  
914  
1667 940  
1886 156  
1435 1264 591  
521  
143  
178  
521  
435  
305  
1264  
SCRG/SIRG 20  
SCWG/SIWG 30, 35  
SCRG/SIRG 25, 32  
914  
1667 940  
1886 156  
1559 1594 714  
521  
83  
178  
521  
435  
140  
1594  
26  
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Dimensions  
and Weights  
Detail A”  
Detail B”  
SCXG-SVX01B-EN  
(Factory  
provided  
for field  
installation)  
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Dimensions  
and Weights  
Installation  
Variable Frequency Drive  
Variable Frequency Drive Dimensions - English - (inches)  
MotorHP  
7.5  
7.5  
10  
10  
15  
15  
20  
20  
25  
Voltage  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
A
9
6 7/8  
9
B
C
8
6 1/8  
8
D
E
F
G
H
J
K
Weight  
26 lbs.  
15 lbs.  
26 lbs.  
26 lbs.  
75 lbs.  
26 lbs.  
75 lbs.  
31 lbs.  
126 lbs.  
75 lbs.  
1
1
1
1
1
/
/
12 3/4  
11 1/4  
12 3/4  
12 3/4  
22  
/
/
/
/
/
/
/
/
12 1/4  
10 1/2  
12 1/4  
12 1/4  
21 1/4  
12 1/4  
21 1/4  
15 7/8  
24 3/4  
21 1/4  
/
8 1/4  
7 1/4  
8 1/4  
8 1/4  
11 1/4  
8 1/4  
11 1/4  
8 1/4  
12 1/8  
11 1/4  
/
2
2
4
8
4
4
8
4
8
4
8
8
4
4
4
4
4
4
4
4
4
8
4
3
1
1
3
1
3
1
3
1
1
3
1
3
1
3
3
1
1
3
1
3
1
7
3
1
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
8
2
2
4
2
4
2
8
2
2
4
2
4
2
8
4
4
8
4
8
4
8
8
1
1
1
1
9
8
3
1
9 5/8  
9
8 1/8  
8
1
1
12 3/4  
22  
16 3/8  
26  
3
1
9 5/8  
9
8 1/8  
8
1
1
3
3
14  
9 5/8  
1
12  
8 1/8  
1
/
3
3
3
1
25  
/
/
22  
/
/
4
4
Variable Frequency Drive Dimensions - Metric (mm)  
MotorHP  
7.5  
7.5  
10  
10  
Voltage  
200V  
460V  
200V  
460V  
A
B
C
D
E
F
6
10  
6
6
G
H
6
10  
6
J
K
6
6
6
6
Weight  
12 kg.  
7 kg.  
12 kg.  
12 kg.  
229  
175  
229  
229  
13  
10  
13  
13  
203  
156  
203  
203  
13  
10  
13  
13  
324  
286  
324  
324  
311  
267  
311  
311  
210  
184  
210  
210  
6
15  
15  
20  
20  
25  
25  
200V  
460V  
200V  
460V  
200V  
460V  
244  
229  
244  
229  
356  
244  
19  
13  
19  
13  
25  
19  
206  
203  
206  
203  
305  
206  
19  
13  
19  
13  
25  
19  
559  
324  
559  
416  
660  
559  
10  
6
10  
6
10  
10  
540  
311  
540  
403  
629  
540  
10  
6
10  
6
22  
10  
286  
210  
286  
210  
308  
10  
6
6
6
6
10  
286  
34 kg.  
12 kg.  
34 kg.  
14 kg.  
57 kg.  
34 kg.  
28  
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Dimensions  
and Weights  
Installation  
Variable Frequency  
Drive with Bypass  
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Dimensions  
and Weights  
Installation  
Variable Frequency Drive With Bypass Dimensions - English - (inches)  
MotorHP  
7.5  
7.5  
10  
10  
15  
15  
20  
20  
25  
Voltage  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
A
B
C
D
E
F
G
H
J
K
L
M
Weight  
126 lbs.  
87 lbs.  
19 1/2 17 1/2 1 7/8  
14 1/2 12 1/4 1 7/8  
19 1/2 17 1/2 1 7/8  
19 1/2 17 1/2 1 7/8  
41  
35  
41  
41  
49  
41  
49  
41  
49  
49  
39 3/4 13 1/2 12  
33 3/4 13 1/2 12  
39 3/4 13 1/2 12  
39 3/4 13 1/2 12  
47 7/8 16 3/8 14 7/8  
39 3/4 13 1/2 12  
47 7/8 16 3/8 14 7/8  
39 3/4 13 1/2 12  
47 7/8 16 3/8 14 7/8  
47 7/8 16 3/8 14 7/8  
3 1/4  
3 1/4  
3 1/4  
3 1/4  
6
38  
32  
38  
38  
46 3/8 --  
38  
46 3/8 --  
38  
46 3/8 --  
46 3/8 --  
1 1/4  
1 1/4  
1 1/4  
1 1/4  
20 1/2 2 3/8  
14 3/4 2 3/8  
20 1/2 2 3/8  
20 1/2 2 3/8  
20 1/2 --  
126 lbs.  
126 lbs.  
180 lbs.  
126 lbs.  
180 lbs.  
126 lbs.  
180 lbs.  
180 lbs.  
20  
19 1/2 17 1/2 1 7/8  
20 18  
1 7/8  
19 1/2 17 1/2 1 7/8  
20  
20  
18  
1 7/8  
3 1/4  
6
3 1/4  
6
1 1/4  
20 1/2 2 3/8  
20 1/2 --  
1 1/4  
20 1/2 2 3/8  
20 1/2 --  
18  
18  
1 7/8  
1 7/8  
25  
6
20 1/2 --  
Variable Frequency Drive With Bypass Dimensions - Metric (mm)  
MotorHP  
7.5  
7.5  
10  
10  
15  
15  
20  
20  
25  
Voltage  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
200V  
460V  
A
B
C
D
E
F
G
H
83  
83  
83  
83  
152  
83  
152  
83  
152  
152  
J
K
L
M
60  
60  
60  
60  
--  
60  
--  
60  
--  
Weight  
57 kg.  
40 kg.  
57 kg.  
57 kg.  
82 kg.  
57 kg.  
82 kg.  
57 kg.  
82 kg.  
82 kg.  
495  
362  
495  
495  
508  
495  
508  
495  
508  
508  
445  
311  
445  
445  
457  
445  
457  
445  
457  
457  
48  
48  
48  
48  
48  
48  
48  
48  
48  
48  
1041 1010 343  
889 857 343  
305  
305  
305  
305  
378  
305  
378  
305  
378  
378  
965  
813  
965  
965  
1178 --  
965  
1178 --  
965  
1178 --  
1178 --  
38  
38  
38  
38  
521  
375  
521  
521  
521  
521  
521  
521  
521  
521  
1041 1010 343  
1041 1010 343  
1244 1216 416  
1041 1010 343  
1244 1216 416  
1041 1010 343  
1244 1216 416  
1244 1216 416  
38  
38  
25  
--  
30  
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Dimensions  
and Weights  
Installation  
Flexible Horizontal Discharge  
Plenum  
Flexible Horizontal Discharge Plenum Dimensions - English - (inches)  
20-35Tons  
LowHeight  
StandardHeight  
A
35  
35  
B
C
17 1/4 86 1/2  
1
1
25 /4 86 /2  
Flexible Horizontal Discharge Plenum Dimensions - Metric (mm)  
20-35Tons  
A
B
C
LowHeight  
StandardHeight  
889  
889  
438  
641  
2197  
2197  
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Dimensions  
and Weights  
Installation  
Table I-DW-1. Unit Weights, English - SCWG/SCRG/SIWG/SIRG  
2-Row  
Waterside  
4-Row  
Waterside  
Unit  
Size  
Base  
Airside  
Heating  
Weight  
lbs.  
Economizer  
lbs.  
Economizer  
lbs.  
Economizer  
lbs.  
Coil Box  
lbs.  
SCWG/SIWG  
20  
25  
30  
35  
2620  
2730  
2864  
3000  
273  
273  
273  
273  
488  
488  
488  
488  
584  
584  
584  
584  
460  
460  
460  
460  
SCRG/SIRG  
Notes:  
20  
25  
32  
2344  
2479  
2614  
273  
273  
273  
488  
488  
488  
584  
584  
584  
460  
460  
460  
1. All unit weights include refrigerant, water, inlet guide vanes and controllers, electric heat and valves.  
2. Add 150 lbs. to total weight to obtain approximate shipping weight.  
3. Flexible horizontal discharge plenum option weights:  
Standard height plenum = 352 lbs.  
Low height plenum = 262 lbs.  
4. VFD weights are on pages 28 and 30.  
Table I-DW-2. Unit Weights, Metric - SCWG//SIWG/SCRG/SIRG  
2-Row  
Waterside  
4-Row  
Waterside  
Unit  
Size  
Base  
Airside  
Heating  
Weight  
Kg  
1365  
1400  
1500  
1640  
Economizer  
Kg  
Economizer  
Economizer  
Kg  
Coil Box  
Kg  
210  
210  
210  
Kg  
65  
65  
85  
130  
SCWG/SIWG  
20  
25  
30  
35  
195  
195  
225  
225  
155  
155  
175  
230  
210  
SCRG/SIRG  
Notes:  
20  
25  
32  
1325  
1425  
1530  
195  
225  
225  
65  
85  
130  
155  
175  
230  
210  
210  
210  
1. All unit weights include refrigerant, water, inlet guide vanes and controllers, electric heat and valves.  
2. Add 68 kg. to total weight to obtain approximate shipping weight.  
3. Flexible horizontal discharge plenum option weights:  
Standard height plenum = 160 kg  
Low height plenum = 119 kg  
4. VFD weights are on pages 28 and 30.  
32  
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Mechanical  
Requirements  
Installation  
Duct Connections  
unit due to increased noise and excessive  
static losses. Use elbows with splitters or  
turning vanes to minimize static losses.  
ƽ WARNING  
!
Poorly constructed turning vanes may  
cause airflow generated noise. Align the  
fan outlet properly with the ductwork to  
decrease noise levels in the duct and to  
increase fan performance. To complete  
trunk ductwork to theVAV terminal units,  
refer to theVAV box manuals for specific  
requirements. Check total external static  
pressures against fan characteristics to  
be sure the required airflow is available  
throughout the ductwork.  
Disconnect electrical power  
source before servicing the unit.  
Failure to do so may result in  
injury or death from electrical  
shock or entanglement in moving  
parts.  
Return air enters the rear of the unit and  
conditioned supply air discharges  
through the top. Attach supply air  
ductwork directly to the units top panel,  
around the fan discharge opening. A duct  
collar is not provided.  
To achieve maximum acoustical perfor-  
mance, minimize the duct static pressure  
setpoint.  
Note:Units equipped with the flexible  
horizontal discharge plenum option may  
include a duct collar when holes are factory  
cut. If discharge openings are field-cut,  
refer to the “Plenum Installation” section.  
Install all air ducts according to the  
National Fire Protection Association  
standards for the Installation of Air  
Conditioning andVentilation Systems  
other than ResidenceType (NFPA 90A)  
and ResidenceType Warm Air Heating  
and Air Conditioning Systems (NFPA  
90B).  
Make duct connections to the unit with a  
flexible material such as heavy canvas. If  
a fire hazard exists,Trane recommends  
using Flexweave 1000, type FW30 or  
equivalent canvas. Use three inches for  
the return duct and three inches for the  
discharge duct. Keep the material loose  
to absorb fan vibration.  
Figure I-MR-1. Duct connection recommen-  
dations.  
Note: The compressors and fan assembly  
are internally isolated. Therefore, external  
isolation devices (spring mounting  
isolators) are at the discretion of a vibration  
specialist consulted by the building or  
HVAC system designer.  
Run the ductwork straight from the  
opening for a minimum of three fan  
diameters. See Figure I-MR-1. Extend  
remaining ductwork as far as possible  
without changing size or direction. Do not  
make abrupt turns or transitions near the  
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Mechanical  
Requirements  
Installation  
Water Piping  
2. Attach the water supply line to the inlet  
connection, and the return line to the  
outlet connection. Entering and leaving  
water connections for all condensers  
are factory manifolded and require only  
single connections for entering and  
leaving water. If the unit has a  
waterside economizer and/or control  
valves, the factory pipes between these  
components.  
3. If using a cooling tower, refer to Figure  
I-MR-3 on page 35 for a typical piping  
circuit from the unit. For typical city or  
well water piping, see Figure I-MR-4 on  
page 35.  
4. Ensure the water pressure to the unit  
does not exceed 400 psig.  
Condensate Drain Connections  
The condensate drain is internally  
trapped. Condensate drain connections  
are on the units left side. Connect  
condensate drain piping to the 1 1/4NPT  
female fitting, using at least 7/8OD  
copper or 3/4OD iron pipe. Pitch the  
condensate line downward a minimum of  
1/2for each 10' of horizontal run, away  
from the unit. Be sure to install the  
condensate drain Ptrap drain plug.  
Before starting the unit, fill the trap with  
water to prevent negative pressure in the  
fan section from impeding condensate  
flow.To facilitate drain pipe cleaning,  
install plugged tees in place of 90°  
elbows.  
Note: To prevent water damage, install all  
piping drain and vent plugs.  
Condenser Connections  
Condenser water piping knockouts are in  
the lower left end panel. If necessary,  
remove insulation to gain access. All field  
installed piping must conform to  
applicable local, state, and federal codes.  
To complete condenser water  
connections follow the procedure below.  
Note: Four condenser waterline drain  
plugs ship in a bag in the unit’s left end.  
The installer must field install these four  
plugs using pipe thread sealer. An addi-  
tional plug are provided for units with a  
waterside economizer.  
Note: To prevent water pump damage,  
design system piping to provide relief  
when using energy saving waterside  
economizer valves.  
Table I-MR-1. Water Connection Sizes.  
Unit Size  
SXWG 20-35  
Direct Condenser  
1 1/2 NPT  
Factory Piped  
2 1/2 NPT  
1. Install the vent plugs in the economizer  
coil headers and condenser manifolds.  
These plugs ship in a bag with the  
condenser drain plugs.  
Figure I-MR-2. Direct condenser connections.  
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Mechanical  
Requirements  
Installation  
General Waterside Recommendations:  
Cooling Towers  
Cooling tower control affects the unit  
cycle rates. Condenser water  
temperature swings from 10-15 degrees  
F may cause excessive compressor,  
water valve, and unit cycling. Be sure to  
set the tower controls to minimize  
compressor/unit cycling.  
Note: Unit does not have floor drains.  
Units with variable water flow (intermedi-  
ate piping) have a modulating condensing  
pressure control valve that allows  
compressor operation down to entering  
water temperatures of 35 F (2 C).  
Water Temperature Requirements  
Do not allow the entering water  
temperature to go below 54 F (12.2 C) on  
units with constant water flow (basic  
piping). This will cause the compressors  
to shut down and the mechanical cooling  
function will lockout. However, the  
economizer (if enabled) will continue to  
function. The compressors will reset  
when the entering water temperature  
reaches 58 F (15C).  
For more information on constant and  
variable water flow, see the Owners  
section of this manual.  
Note: Units with a waterside economizer  
can be set from the human interface panel  
for variable or constant water flow.  
Waterside Piping Arrangements  
Install a condenser water pump between  
the cooling tower (either open or closed)  
and the self-contained unit. Lay out the  
remainder of the systems condenser  
piping in reverse returns. This helps  
balance the system by equalizing the  
length of supply and return pipes.  
Multistory buildings may use a direct  
return system with balancing valves at  
each floor.  
Install the supply riser and its return in  
close proximity. Furnish both with  
permanent thermometers to check the  
waterside balance during start-up and  
routine maintenance checks.  
Also, include strainers at each pump inlet  
and unit. Install drain valves at the risers  
base to allow drainage points for system  
flushing during start-up and routine  
maintenance. For condenser draining  
and header removal, include a shutoff/  
balancing valve on the entering and  
leaving waterside pipes, drain tees, and  
unions of each unit. Also, install a shutoff  
valve on the unit entering water pipe for  
condenser draining.  
Figure I-MR-3. Condenser water piping components for cooling tower system.  
Figure I-MR-4. Typical water piping for city or well water system.  
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Mechanical  
Requirements  
Installation  
Refrigerant Piping (Air-Cooled  
Units Only)  
The maximum line pressure design of  
each refrigerant circuit is 3 psig. Include  
the following items when designing  
refrigerant piping: oil traps, dual risers, oil  
return, etc. Refer to the Trane  
of the interior surfaces. Use a pressure  
regulating valve or flow meter to  
control the flow.  
2. Ensure that the tubing surfaces  
requiring brazing are clean, and that the  
tube ends are carefully reamed to  
remove any burrs.  
Reciprocating Refrigeration Manual for  
proper line sizing and layout.  
3. Make sure the inner and outer tubes of  
the joint are symmetrical and have a  
close clearance, providing an easy slip’  
fit. If the joint is too loose, the  
connections tensile strength is  
significantly reduced. Ensure the  
overlap distance is equal to the inner  
tube diameter.  
See the Start Upsection on page 74 of  
this manual for instructions on refrigerant  
evacuation, charging, and superheat  
measurement. Leak-test the entire  
refrigeration system after all piping is  
complete.  
Leak Test (Remote Air-cooled Units  
Only)  
4. Wrap each refrigerant line component  
with a wet cloth to keep it cool during  
brazing. Excessive heat can damage  
the internal components.  
Units ship with a holding charge of dry  
nitrogen. Before installing the unit  
refrigerant piping, momentarily depress  
either the suction or discharge line access  
valve to verify the holding charge has not  
been lost. If no nitrogen escapes the  
access valve, leak-test the entire  
refrigerant system to determine the leak  
source. Use a halogen leak detector, a  
halide torch, or soap bubbles to leak test.  
After finding a leak, remove the test  
pressure and repair the leak. Retest the  
unit to ensure all leaks are repaired.  
5. If using flux, apply it sparingly to the  
joint. Excess flux will contaminate the  
refrigerant system.  
6. Apply heat evenly over the length and  
circumference of the joint.  
7. Begin brazing when the joint is hot  
enough to melt the brazing rod. The hot  
copper tubing, not the flame, should  
melt the rod.  
Brazing Procedures  
Proper brazing techniques are essential  
when installing refrigerant piping. The  
following factors should be kept in mind  
when forming sweat connections:  
8. Continue to apply heat evenly around  
the joint circumference until the brazing  
material is drawn into the joint by  
capillary action, making a mechanically  
sound and gas-tight connection.  
1. When heating copper in the presence  
of air, copper oxide forms.To prevent  
copper oxide from forming inside the  
tubing during brazing, sweep an inert  
gas, such as dry nitrogen, through the  
tubing. A nitrogen flow of 6 to 10 cubic  
feet per hour is sufficient to displace the  
air in the tubing and prevent oxidation  
9. Visually inspect the connection after  
brazing to locate any pinholes or  
crevices in the joint. Use a mirror if joint  
locations are difficult to see.  
36  
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Electrical  
Requirements  
Installation  
Unit Wiring Diagrams  
Voltage Imbalance  
Read the voltage at the compressor  
terminals to determine if it is balanced.  
Voltage imbalance on three phase  
systems can cause motor overheating  
and premature failure. The maximum  
allowable imbalance is 2.0%. Voltage  
imbalance is defined as 100 times the  
sum of the deviation of the three voltages  
from the average (without regard to sign)  
divided by the average voltage. For  
example, if the three measured voltages  
are 221, 230, and 227, the average  
voltage would be:  
Specific unit wiring diagrams are  
provided on the inside of the control  
panel door. Use these diagrams for  
connections or trouble analysis.  
Supply Power Wiring  
It is the installers responsibility to provide  
power supply wiring to the unit terminal  
block or the non-fused disconnect switch  
option. Wiring should conform to NEC and  
all applicable code requirements.  
Bring supply wiring through the knockout  
in the lower left side of the unit control  
panel. Connect the three phase wires to  
the power terminal block or the non-  
fused disconnect switch in the control box  
terminals. Refer to specific wiring  
diagrams and fuse information in the  
units control panel.  
(221 + 230 + 227) = 226 volts  
3
The percentage of voltage imbalance is  
then:  
100 * (226-221) = 2.2%  
226  
Control Power  
In this example, 2.2% imbalance is not  
acceptable. Whenever a voltage  
imbalance of more than 2.0% exists,  
check the voltage at the unit disconnect  
switch. If the imbalance at the unit  
disconnect switch does not exceed 2.0%,  
faulty unit wiring is causing the  
imbalance. Conduct a thorough  
inspection of the unit electrical wiring  
connections to locate the fault, and make  
any repairs necessary.  
ƽ CAUTION  
!
Disconnect electrical power  
source to prevent injury or death  
from electrical shock.  
ƽ CAUTION  
!
Use only copper conductors for  
electrical unit connections to  
prevent equipment damage.  
Access the connection terminal block  
through the control panel on the units  
upper left side. All wiring should conform  
to NEC and applicable local code  
requirements.  
ƽ CAUTION  
!
Be sure all wiring connections are secure.  
Reference the unit specific diagrams  
inside the control panel.  
Correct phase sequence is  
critical. If phase sequence of the  
incoming line voltage is not  
correct, it may result in motor  
damage.  
ƽ CAUTION  
!
Unit transformers are sized to  
provide power to the unit only.  
Do not use these transformers to  
supply power to field equipment.  
Field connections to these  
transformers may create  
Voltage Range  
Voltages must be within +- 10% the  
nameplate voltage. Ensure the unit  
voltage is balanced by measuring at the  
compressor terminals. Voltage imbalance  
on three phase systems can cause motor  
overheating and premature failure.  
Maximum allowable imbalance is 2.0  
percent.  
immediate or premature  
component failures.  
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Electrical  
Requirements  
Installation  
Selection Procedures  
Table I-ER-1. Number of Compressors per Unit  
RLA = Rated Load Amps  
SCWG/SIWG 20  
SCRG/SIRG 20  
25  
30  
25  
1
35  
32  
-
Compressor LRA = Locked Rotor Amps  
Fan Motor LRA = Locked Rotor Amps,  
N.E.C.Table 430 - 150  
10HP  
2
-
2
-
15HP  
1
2
FLA = Full Load Amps, N.E.C.  
Table 430 - 150  
Table I-ER-2. SCWG/SIWG Compressor Motor Data  
Voltage utilization range is 10 percent  
200V  
460V  
575V  
575V  
Determination of minimum circuit  
ampacity (MCA).  
MCA = 1.25 x largest motor amps/VFD  
amps (FLA or RLA) + the sum of the  
remaining motor amps.  
HP  
10  
15  
RLA  
33.1  
46.9  
LRA  
269  
409  
RLA  
14.4  
20.4  
LRA  
117  
178  
RLA  
11.5  
16.4  
LRA  
94  
143  
Table I-ER-3. SCRG/SIRG Compressor Motor Data  
Determination of maximum fuse size  
(MFS) and maximum circuit breaker size  
(MCB).  
MFS and MCB = 2.25 x largest motor  
amps (FLA or RLA) + the sum of the  
remaining motor amps.  
200V  
460V  
HP  
10  
15  
RLA  
38.4  
55.0  
LRA  
269  
409  
RLA  
16.7  
24.1  
LRA  
117  
178  
RLA  
13.4  
19.1  
LRA  
94  
143  
Table I-ER-4. Fan without VFD  
If the rating value determined does not  
equal a standard current rating of over  
current protective device, use the next  
lower standard rating for the marked  
maximum rating.  
200V  
460V  
575V  
HP  
5
FLA  
LRA  
105  
152  
193  
290  
373  
469  
FLA  
LRA  
FLA  
LRA  
16.1  
25.0  
32.9  
44.8  
61.0  
74.0  
6.7  
46  
5.4  
37  
7.5  
10  
15  
20  
25  
10.8  
14.2  
20.3  
25.0  
31.0  
66  
84  
126  
162  
204  
8.2  
54  
66  
102  
132  
162  
11.4  
16.2  
20.0  
24.2  
For units with the dual power option,  
there are two circuits that need calcula-  
tions using the formulas above:  
circuit #1 - fans  
circuit #2 - compressors  
Table I-ER-5. Fan with VFD  
200V  
460V  
If the rating value determined does not  
equal a standard current rating of over  
current protective device, use the next  
lower standard rating for the marked  
maximum rating.  
HP  
7.5  
10  
15  
20  
25  
FLA  
LRA  
152  
193  
290  
373  
469  
FLA  
14.3  
18.2  
25.3  
32.0  
32.7  
LRA  
66  
84  
126  
162  
204  
29.0  
38.3  
42.7  
55.2  
67.8  
Table I-ER-6. Electric Heat - Single Stage  
SCWG/SIWG  
SCRG/SIRG  
Heat  
Kw  
16  
20  
24  
26  
28  
200V  
460V  
Amps  
19.6  
24.2  
29.0  
31.6  
34.0  
Size  
20  
25  
30  
-
Size  
20  
25  
-
32  
-
Amps  
44.8  
55.6  
66.8  
72.4  
78  
35  
Note:  
Electric heat amperage should not be considered when determining minimum circuit ampacity. The current of the  
unit in the heating mode will not exceed the current of the unit in the cooling mode.  
38  
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Pre-Startup  
Requirements  
Installation  
Pre-Startup Procedures  
Before starting up units perform the  
following procedures to ensure proper  
unit operation.  
Unit Protective Covers  
Remove the shipping protection  
coverings from the human interface  
panel (HI) at the control panel, the filter  
box (or air inlet opening), the discharge  
air opening, and optional variable  
frequency drive (VFD).  
Compressor Isolators  
Loosen compressor isolator mounting  
bolts and remove shipping bracket from  
beneath the compressor feet. Retighten  
isolator mounting bolts.Torque to 18 ft.  
lbs. (+ 2 ft. Lbs.)  
Supply Fan Isolators  
Remove the shipping channels and  
mounting bolts from beneath the fan. See  
Figure I-PR-1. Open both fan  
compartment access doors to access the  
channels. The unit has six isolator  
mounting points. See Figure I-PR-2.  
Figure I-PR-1. Supply fan horizontal isolation shipping bracket.  
While keeping the fan mounting frame  
level, turn the fan isolator height adjusting  
bolts until the fan housing P-gasket  
compresses 1/4against the roof transi-  
tion piece. See Figure I-PR-1.  
Figure I-PR-2. Fan isolator locations.  
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Pre-Startup  
Requirements  
Installation  
Unit Vibration Isolator Option  
Note: The compressors and fan assembly  
are internally isolated. Therefore, external  
isolation devices (spring mounting  
isolators) are at the discretion of a vibration  
specialist consulted by the building or  
HVAC system designer. In general, the  
Trane Company does not recommend  
double-isolation.  
upper housing of the spring isolators to  
rest on the lower housing. Maintain  
Vibration isolation is not necessary for the  
unit since the factory internally isolates  
the fan and compressors, thus creating  
double isolation.TheTrane Company  
strongly recommends that you consult a  
vibration specialist when considering  
double isolation. If job requirements  
dictate unit isolators, use a housed-spring  
isolator with a locating pin. Factory-  
provided unit isolators are type CP and  
indicate the spring number on the outer  
housing. See Figure I-PR-3. Set the  
spring-type vibration isolators in position  
before completing electrical, piping, or  
duct connections. Units require four  
isolators per unit. Reference the isolator  
placement sheet that ships with the  
isolators to indicate proper placement.  
1
1
clearances between /4 to /2. To  
increase the clearance, lift the unit off  
the isolator and turn the leveling bolt  
counterclockwise. Verify that the unit is  
level and the housing clearances are  
correct. The maximum allowable  
difference between isolator heights is  
1/4. Shim as required under the  
isolators.  
Note: The unit is equipped with a posi-  
tively sloped drain pan to help indoor air  
quality (IAQ) and does not require one  
corner of the unit to be pitched.  
Unit Isolator Installation Procedure  
Follow the procedure below to install  
isolators:  
1. Position the isolators under the unit  
base referring to the isolator placement  
sheet that ships with the unit isolators.  
Lift one end of the unit at a time to  
position the isolators. Fasten the  
isolators to the floor using anchor bolts.  
2. Level the unit by adjusting the isolator  
heights. Unit weight may cause the  
Figure I-PR-3. Optional spring-flex vibration isolator (type CP-1) for unit isolation.  
40  
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Pre-Startup  
Requirements  
Installation  
Plenum  
Treat field-cut holes to prevent fiberglass  
from entering the airstream.  
Before installing the plenum attach the  
insulation strip that ships with the plenum.  
See Figure I-PR-4 for proper insulation  
location. Align the plenum front with the  
control panel side of the unit. Using the  
strips and screws provided, secure the  
plenum to the unit.  
Note: Plenum insulation must be applied  
properly to prevent air bypass around the  
plenum. See Figure I-PR-4.  
ƽ CAUTION  
!
Do not remove more than two  
nonadjacent panels at one time.  
Failure to do so will cause the  
plenum frame to collapse and may  
cause personal injury.  
Plenum BottomView  
Dashed line indicates correct insulation placement.  
Figure I-PR-4. Correct plenum insulation placement.  
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Pre-Startup  
Requirements  
Installation  
Waterside Economizer  
Installation Procedure  
6. Align economizer holes with the holes  
in the unit channel. Install screws in the  
top (6x) and bottom (6x) of the  
1. Loosen and pull all end devices that  
go through the bushing or the filter  
rack (upper right corner of rack).  
2. Remove the filter rack from the back  
of the unit by removing the 1/4hex  
head screws from the top and bottom  
of the filter rack assembly.The filter  
rack assembly will hang on the unit  
when the screws are removed.  
Remove the filter rack by lifting it up  
off the unit.  
3. Remove the economizer from the  
crate and position it behind the unit  
with the headers on the left side,  
when facing the back of the unit.  
Remove the plastic envelope that is  
taped to the economizer box  
assembly.This envelope contains the  
gasket that must be installed onto the  
vertical side flanges of the box.  
4. Install the pressure sensitive gasket to  
the unit side of the vertical flange on  
the economizer box.  
5. Hang the economizer on the unit as  
shown in Figure I-PR-5. Lift the  
economizer by using the holes  
provided in the top panel of the  
economizer.  
7. Remove the units rear middle panel  
and unbraze the two copper pipes in  
the 2 5/8water pipe. Do not remove  
the pipe outlet blockoff panel.  
8. Remove the economizer tubing  
assemblies from the shipping box.  
Check ship-separate parts against  
those shown in Figures I-PR-6, I-PR-7, I-  
PR-8, and I-PR-9. Face the front of the  
unit to see which side the water pipe  
exits to determine if the unit has either  
right or left-hand piping.  
9. Assemble tubing as shown in Figure I-  
PR-6 or I-PR-9.Tack all tubes in place  
before brazing to ensure proper fit-up.  
For right-hand piped units, install the  
ball valve actuator assembly and  
actuator. Refer to the unit wiring  
diagram for wiring connection points.  
10. Install the pipe insulation on all pipe  
line to prevent sweating. Install the  
rear middle panels. Re-install the filter  
rack on the back of the economizer coil  
box and affix with screws provided.  
Figure I-PR-5. Installing the waterside economizer.  
42  
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Pre-Startup  
Requirements  
Installation  
Waterside Economizer with  
Left-Hand Factory Piping  
Components  
Figure
Table I-PR-1. Waterside Economizer Ship-Separate Parts List, LH  
Item Part Description  
Factory  
Piping  
Left-Hand  
Item Part #  
Qty.  
Description  
A
B
C
D
E
F
Assembly #1  
Assembly #2  
Assembly #3  
Assembly #4  
Tube; 2 5/8x 16 7/8”  
Tube; 2 5/8x 22 5/8  
Figure I-PR-6. Detail view of ship-separate  
tubing assemblies for waterside econo-  
mizer left-hand piping.  
4001  
X17110026250  
4003  
4002  
4009  
X21040098390  
X21080406030  
X16120203570  
X17150027060  
X17170031210  
4738  
2
5
1
1
1
Tube; 2 5/8x 9”  
Elbow; 2 5/8x 2 5/8”  
Tube; 2 5/8x 26 15/16”  
Tube; 2 5/8x 34 3/16”  
*Tube; 2 5/8x 16 7/8”  
10 ft. *Gasket  
1
1
1
1
1
1
1
*Insulation; 2 5/8Rubatex  
Plug; 1 1/2Brass  
Bushing; 2 1/2ftg. x 1 1/2”  
Tee; 2 5/8x 2 1/8x 2 5/8”  
*Tube; 2 5/8x 19 13/16”  
Tube; 2 5/8x 14 1/2”  
4007  
4006  
Tube; 2 5/8x 19 13/16”  
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Pre-Startup  
Requirements  
Installation  
Waterside Economizer with  
Right-Hand Factory Piping  
Components  
Table I-PR-2. Waterside Economizer Ship-Separate Parts List, RH  
Right-Hand  
4001  
4607  
X17110026250  
4605  
X153301770100  
4008  
X17170031210  
X16120203570  
X17150027060  
4007  
4606  
4603  
1
1
5
2
1
1
1
1
1
1
1
1
1
1
Tube; 2 5/8x 9”  
Tube; 2 5/8x 17”  
Elbow; 2 5/8x 2 5/8”  
Tube; 2 5/8x 9 1/2”  
Water Valve  
*Tube; 2 5/8x 20 1/4”  
Tee; 2 5/8x 2 1/8x 2 5/8”  
Brass Plug, 1 1/2”  
Bushing; 2 1/8ftg. x 1 1/2”  
Tube; 2 5/8x 14 1/2”  
Tube; 2 5/8x 62  
*Tube; 2 5/8x 11 3/4”  
Tube; 2 5/8x 19 3/4”  
*Actuator Assembly  
4006  
4460-7575  
X21080406030  
X21040098390  
14 ft. *RubatexInsulation  
10 ft. *Gasket  
*These items require field assembly.  
Item Part Description  
A
B
C
D
E
Assembly #1  
Assembly #2  
Assembly #3  
Assembly #4  
Tube; 2 5/8x 11 3/4”  
Tube; 2 5/8x 20 1/4”  
ActuatorAssembly  
F
G
Figure I-PR-8. Waterside economizer with right-hand factory piping tubing assembly.  
Assembly 1  
Assembly 3  
Assembly 4  
Assembly 2  
Figure I-PR-9. Detail view of ship-separate tubing assemblies for waterside economizer right-hand factory piping.  
44  
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Pre-Startup  
Requirements  
Installation  
Hydronic Coil Installation  
3. Install the pressure sensitive gasket to  
the unit side of the vertical flange on the  
coil box in two places.  
These instructions are for steam and hot  
water coil installation. The hydronic coil  
assembly has a full coil, piping, a modu-  
lating temperature control valve, and a  
disc temperature limit device located in  
the unit near the fan on the motor frame.  
Hydronic coils are available with either  
right or left-hand pipe connections. Piping  
connections are identical to the unit  
piping. For example, if you have right-  
hand unit piping, the hydronic coil will  
have right-hand connections. The  
4. Using 2x 1/2standard thread  
eyebolts, thread into the coil lift plates to  
raise the coil up to the height necessary  
to attach it to the unit. The top panel has  
a Jhook on it to allow hanging,  
similar to the filter rack. Align the holes  
so that the coil hangs on the unit. If the  
unit has the dirty filter option, connect  
the static pressure tube to the unit  
before bolting the coil in place. Locate  
the static pressure tubing on the unit  
evaporator coil and route through the  
knockout in the top corner of the coil  
box.  
hydronic coil assembly has temperature  
controls to keep the units internal cabinet  
temperature below 105 F to prevent  
motor and bearing damage.  
5. Align the hydronic coil with the holes in  
the unit channel or waterside  
Installation Procedure  
1. Remove filter rack from the back of the  
unit. Remove the 1/4-inch hex head  
screws from the top and bottom of the  
filter rack assembly.The filter rack  
assembly will hang on the unit when  
the screws are removed. The filter rack  
can now be removed by lifting up on  
the filter rack.  
2. Remove the hydronic coil from the  
crate and position it behind the unit with  
the open side facing the unit evaporator  
coil inlet. Also, remove the plastic  
envelope that is taped to the coil box  
assembly.This envelope contains the  
mounting screws needed to attach the  
coil box to the unit and the gasket  
required on the vertical side flanges of  
the box.  
economizer option. Move the coil box  
up against the unit and install using six  
mounting screws in the top and six in  
the bottom of the coil box.  
6. Remove the valve and pipe cover on  
the coil box. Connect the wires that are  
coiled in the coil box, referring to the  
wiring diagram installed on the unit  
control panel door. Route wires into the  
unit through knockouts in the top of the  
box.  
7. Reinstall the filter rack on the back of  
the heating coil rack. If the unit has the  
waterside economizer option, the filter  
rack will require additional support legs.  
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Pre-Startup  
Requirements  
Installation  
Electric Heat Installation  
4. Use the hole pattern in the electric heat  
as a template for marking and drilling  
3/16diameter holes in the unit.  
ƽ WARNING  
!
The electric heat option consists of a  
single stage heater and is used in  
IntelliPak units or units with a field-  
Disconnect electrical power  
5. Bolt the electric heaters to the unit  
source before wiring electric heat  
to unit to prevent risk of injury or  
death from electrical shock.  
using 1/4sheetmetal screws.  
installed thermostat. The electric heater  
ships separate for field installation and  
wiring. Available heater kW per unit size  
is listed inTable I-PR-3. Electric heat can  
be installed on units with either a vertical  
or horizontal discharge. However, it  
cannot be installed on units with plenums.  
See Figure I-PR-10, Tables I-PR-4, and  
I-PR-5 for electric heat dimensional data.  
Note: It is very important that electric  
heaters are selected based on unit voltage  
and tonnage because discharge opening  
sizes vary by unit tonnage.  
2. Punch out the appropriate knockouts in  
the electric heater control box and on  
the units left side panel. Run the wires  
down the side of the unit from the  
heater to the lower unit control box.  
Place the wire in conduit in accordance  
with local code.  
Electric Heat Coil Wiring Procedure  
1. Before wiring the electric heater,  
remove the unit wiring diagram from  
the unit control panel and refer to the  
connection points.  
Table I-PR-3. Available Electric Heat kW  
Unit Size  
20Tons  
25Tons  
30Tons  
32Tons  
35Tons  
Heater kW  
ƽ CAUTION  
!
Use only copper conductors for  
electrical connections to prevent  
equipment damage.  
16  
20  
24  
26  
28  
Installation Procedure  
1. Remove the fan discharge shipping  
covers, if they have not already been  
removed.  
2. Install the open-cell gasket around the  
discharge opening on the heater.  
3. Position the electric heater so that the  
unit fan discharge openings line up with  
the electric heater openings. For a  
vertical discharge unit, position the  
electric heater as shown in Figure I-PR-  
10.  
Figure I-PR-11. Electric heater dimensions.  
Table I-PR-4. Electric Heat Dimensions - English - (inches)  
Unit Size  
20Tons  
25Tons  
B1  
B2  
Z
10 3/4  
12 1/4  
14 3/4  
15 5/8  
15 5/8  
15 5/8  
27 3/4  
26 3/4  
23 3/4  
30, 32, 35Tons  
Table I-PR-5. Electric Heat Dimensions - Metric - (mm)  
Unit Size  
20Tons  
25Tons  
B1  
B2  
Z
273  
311  
375  
397  
397  
397  
705  
679  
603  
Figure I-PR-10. Vertical discharge electric  
heat installation.  
30, 32, 35Tons  
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Pre-Startup  
Requirements  
Installation  
______________________________________________________________  
Variable Frequency Drive  
Option (VFD)  
ƽ CAUTION  
!
Use only copper conductors for  
electrical unit connections to  
prevent equipment damage.  
The variable frequency drive (VFD)  
option can only be used with IntelliPak  
units. The VFD and VFD w/bypass is  
available from 7.5 to 25 hp and is a  
Square D model Altivar 58. AllVFDs are  
pre-configured and run-tested at the  
factory prior to shipping. The VFD is wall  
mounted. For more information on the  
VFD, see the manuals that ship with each  
VFD: Altivar 58 Adjustable Speed Drive  
Controllers Keypad Display and  
VFD Mounting Requirements  
Proper location of the VFD is important to  
achieve proper performance and normal  
operating life. Installation must be in an  
area where it will be protected from:  
Direct sunlight, rain or moisture.  
Corrosive gases or liquids.  
Altivar 58 Adjustable Speed Drive  
Controllers Installation GuideType H  
Controllers.  
Vibration, airborne dust, or metallic  
particles.  
For effective cooling as well as proper  
maintenance, install the VFD vertically to  
the ground using four mounting screws.  
There must be a minimum eight inch  
clearance above and below the VFD. A  
minimum two inch clearance is required  
on each side.  
ƽ WARNING  
!
Control and line voltage wiring  
from the VFD to the unit must be  
in accordance with all local and  
National Electric Codes. Do not  
touch circuit components until  
main power has been turned off  
and “charge” lamp is  
extinguished. The capacitors are  
still charged and can be quite  
dangerous.  
Also, allow enough clearance for opening  
theVFD cabinet door.This will ensure  
sufficient air space for cooling.  
Refer to the Dimensions andWeights”  
sections on pages 28-30 forVFD  
dimensions and weights.  
VFD Electrical Installation Procedure  
Refer to the National Electric Code,  
section 310-16 for sizing wires 4B - 9B. All  
other control wires should be twisted  
shielded or twisted pair shielded, 20 - 14  
AWG, with lead length not to exceed 164  
feet. When using shielded wire, the shield  
sheath must be connected at theVFD  
only. The connection on units withVFD  
only is J13-S. On units withVFD w/  
ƽ WARNING  
!
Disconnect electrical power  
source to prevent injury or death  
from electric shock. Do not  
connect or disconnect wires and  
connectors while power is  
applied to the circuit.  
bypass, the connection is ITB1-10.  
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Pre-Startup  
Requirements  
Installation  
Airside Economizer Installation  
Unit Handling  
1. Hoist the damper cabinet to the  
installation location with straps  
positioned under the skid as shown in  
Figure I-PR-12. Use spreader bars to  
prevent unit damage during lifting.  
2. With the damper cabinet at its final  
location (near the unit), remove the  
screws securing it to the skid from the  
side flanges. Retain these screws for  
later use.  
Unit Preparation  
3.The support legs are secured to the  
skid, and the hanging bracket is secured  
with wire ties to an inside flange near  
the cabinets base. Remove the  
C-channel collar and install it on the unit,  
if not already installed.  
Figure I-PR-12. Proper lifting of the airside economizer.  
10. Lower the damper cabinet until the  
holes in its side flanges are aligned with  
the holes in the C-channel collar. Install  
screws removed in step 3 through the  
damper cabinets side flanges and into  
the C-channels corresponding holes.  
13. Cabinets withTRAQ™ dampers  
only: Unroll the two rolls of pneumatic  
tubing located inside the damper  
cabinet. Route these tubes through the  
cabinets front upper panel (0.25 dia.  
holes provided). Connect them to the  
two pneumatic tubes protruding from  
the customer electrical connection  
panel on the unit. Be sure to connect like  
tubes to each other (black to black,  
white stripe to white stripe).  
4. Remove the roll of 1/8thick gasket  
from the damper cabinets W-supports,  
and apply it to the C-channel collar  
mounted on the rear of the unit. This  
gasket will provide a seal between the  
damper cabinet and the unit.  
11. Attach ductwork to the top and back  
dampers according to local codes.  
5. Attach the legs (with screws provided)  
to the leg brackets located on the  
dampers base.  
Field Wiring Connections  
12. Open the damper cabinets door and  
connect the factory-provided plug  
from the actuator to the factory-  
provided plug in the units filter  
section.  
14. Cabinets with TRAQ™ dampers  
only: Locate the bulletsensor and  
rolled up wiring in the units filter  
section. Route it into the damper  
cabinet and insert the sensor into the  
sensor mounting clip attached to  
underside of one of theTraq™  
dampers.  
6. Attach a field-provided clevis of  
suitable strength ( > 1/2), to each of the  
corner lifting brackets through the  
7/8diameter holes.  
7. Attach to the clevises a means of lifting  
the damper cabinet from its skid.  
Unit Installation  
8. Slowly raise the damper cabinet from  
its skid.  
9. Attach the hanging bracket across the  
front of the damper cabinet. Position it  
with its short flange pointing to four  
oclock, and secure it with screws  
provided. See Figure I-PR-13.  
10. Lift the damper cabinet and position it  
such that the hanging bracket is  
positioned over the units C-channel  
collar.  
Figure I-PR-13. Proper installation of the airside economizer option.  
48  
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Pre-Startup  
Requirements  
Installation  
Static Pressure Transducer  
Installation (VAV units only)  
Installing theTransducer  
Complete the following procedure to  
properly install the inlet guide vane static  
pressure transducer.  
Supply air static pressure controls the  
inlet guide vane andVFD options. A static  
pressure head assembly ships separate  
in the control panel for field installation in  
the supply air duct work.The installer is  
responsible for providing pneumatic  
tubing.  
1. Mount the pressure sensing head  
assembly in the duct so that the sensing  
tip is in the middle of the duct, and  
perpendicular to the airflow.This will  
provide proper pressure measurement.  
See Figure I-PR-14.  
2. Connect the pneumatic tubing from the  
sensing head to the push-on tubing  
connection in the control panel. Use a  
plastic static pickup tubing. Do not  
exceed 250 feet for 1/4OD tubing or  
500 feet for 3/8OD tubing.  
Transducer Location  
Place the head assembly in an area of the  
ductwork that will provide an average  
and evenly distributed airflow pattern.  
Use the following guidelines to determine  
an appropriate installation location.  
1. Locate the static head assembly about  
two-thirds to three- fourths of the way  
down the longest duct run, in an area  
approximately 10 duct diameters  
downstream and 2 duct diameters  
upstream of any major interferences,  
turns, or changes in duct diameter.  
2. When installing pneumatic tubing  
between the head assembly and  
transducer in the control panel, do not  
exceed 250 feet for 1/4OD tubing or  
500 feet for 3/8OD tubing.  
The transducer inside the control panel  
picks up low side or reference pressure.  
Note: If plastic tubing pulls away from a  
connection, trim it back before replacing it  
on the fitting. Stretched tubing may leak  
and cause faulty control.  
Figure I-PR-14. Static pressure sensor installation.  
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Pre-Startup  
Requirements  
Installation  
Remote Mounted Thermostat  
Option  
Mount the thermostat in the largest  
not exceed 1 ohm.Table I-PR-6 provides  
recommended wire sizes for length of  
run.  
space occupied by the most people for  
the best average temperature sensing.  
The thermostat should be mounted about  
5 feet from the floor in contact with freely  
circulating air, but not with major drafts.  
Wiring the RemoteAir-cooled CCRC and  
SCRG  
The SCRG/SIRG air-cooled condenser  
should be wired to the control panel of  
the SCRG/SIRG unit to ensure proper  
system operation. Reference unit wiring  
diagrams for correct terminal locations.  
Table I-PR-3 provides recommended  
wires sizes for length of run.  
Avoid the following areas:  
Behind doors or in corners where ther is  
no free circulation.  
Locations where the suns rays or  
infrared radiation from appliances or  
fireplaces may affect thermostat  
operation.  
Table I-PR-6. Control Wire Size and Maxi-  
mum Length  
Surfaces subject to vibration.  
On walls that contact outside air.  
Adjacent to or in line with conditioned air  
discharge grilles or doorways.  
Wire Gauge  
Max. Wire Length  
30 ft.  
22  
20  
18  
16  
14  
50 ft.  
75 ft.  
125 ft.  
200 ft.  
Remote MountedThermostatWiring  
After the thermostat is mounted, wire the  
thermostat back to the unit control panel  
according to the correct diagram shown  
on inside of panel door.  
The total resistance of the thermostat and  
the control wiring to each terminal must  
50  
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Pre-Startup  
Requirements  
Installation  
Standard with All Units  
Remote Zone Sensor Options  
Zone sensor options are available and can be ordered with the unit or after the unit  
ships. Following is a full description of zone sensors and their functions. Installation  
instructions are on page 53. Instructions for the programmable zone sensor are on  
page 55. Refer toTable O-GI-2 on page 79 for the zone sensor temperature vs.  
resistance coefficient curve.  
BAYSENS017B Description  
This zone sensor module ships with all units, and can be used with BAYSENS019,  
BAYSENS020, or BAYSENS021 remote sensors. When this sensor is wired to one of  
these remote zone sensors, wiring must be 18 AWG shielded twisted pair (Belden 8760  
or equivalent). Refer to the specific zone sensor for wiring details. It provides the  
following features and system control functions:  
Remote temperature sensing in the zone  
Morning warmup sensor  
Zone sensor for ICSsystems  
Zone temperature averaging  
Figure I-PR-15. BAYSENS017  
Zone Temperature Sensor Only  
When used as a remote sensor for standard zone sensor, the thermistor sensor must  
be disabled.  
CV Unit Zone Sensor Option  
BAYSENS008 Description  
This zone sensor module is for use with cooling/heating constant volume units. It has  
four system switch settings (heat, cool, auto, and off) and two fan settings (on and  
auto). The zone sensor provides either manual or automatic changeover control with  
dual setpoint capability.  
BAYSENS008 features and system control functions include:  
System control switch to select heating mode (HEAT), cooling mode (COOL),  
automatic selection of heating or cooling as required (AUTO), or to turn the  
system off (OFF).  
Fan control switch to select automatic fan operation while actively heating  
or cooling (AUTO), or continuous fan operation (ON).  
Dual temperature setpoint levers for setting desired temperature. The blue  
lever controls cooling, and the red lever controls heating.  
Thermometer to indicate temperature in the zone. This indicator is factory  
calibrated.  
Figure I-PR-16. BAYSENS008  
Dual setpoint, manual/automatic  
changeover sensor, Accessory Model  
Number Digit 6 = E  
BAYSENSO21 Description  
VAV Unit Zone Sensor Option  
This zone sensor module is for use withVAV units without night setback. It allows the  
user to control system operation and monitor unit operating status from a remote  
location.The sensor has a system switch, a S/A temperature setpoint indicator, a local  
sensor, and four LEDs.  
BAYSENSO21 features and system control functions include:  
Temperature sensing in the zone  
System control switch with mode setting for "AUTO" and "OFF"  
Supply air single temperature setpoint  
Function status indicator lights:  
SYS ONglows continuously during normal operation, or blinks if system is in  
test mode.  
COOLglows continuously during cooling cycles, or blinks to indicate a  
cooling system failure.  
HEATglows continuously during heating cycles, or blinks to indicate a  
heating system failure.  
SERVICEblinks or glows to indicate a problem. These signals vary  
depending on the particular equipment being used.  
Figure I-PR-17. BAYSENS021  
Single setpoint sensor with system  
function lights, Accessory Model Number  
Digit 6 = H  
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Pre-Startup  
Requirements  
Installation  
BAYSENS010 Description  
CV Unit Zone Sensor Option  
This zone sensor module is for use with cooling/heating constant volume units without  
night setback. It has four system switch settings (heat, cool, auto, and off), two fan  
settings (on and auto), and four LEDs.The zone sensor provides either manual or  
automatic changeover control with dual setpoint capability. In addition, it can be used  
with BAYSENS017.  
BAYSENS010 features and system control functions include:  
System control switch to select heating mode (HEAT), cooling mode (COOL),  
automatic selection of heating or cooling as required (AUTO), or to turn the system  
off (OFF).  
Fan control switch to select automatic fan operation while actively heating or cooling  
(AUTO), or continuous fan operation (ON).  
DualTemperature setpoint levers for setting desired temperature.The blue lever  
controls cooling, and the red lever controls heating.  
Thermometer to indicate temperature in the zone. This indicator is factory calibrated.  
Function status indicator lights:  
Figure I-PR-18 BAYSENS010  
Dual setpoint, manual/automatic  
changeover sensor with system function  
lights, Accessory Model Number Digit 6 = F  
SYSTEM ON glows continuously during normal operation, or blinks if  
system is in test mode.  
COOL glows continuously during cooling cycles, or blinks to indicate a  
cooling system failure.  
HEAT glows continuously during heating cycles, or blinks to indicate a  
heating system failure.  
SERVICE blinks or glows to indicate a problem. These signals vary  
depending on the particular equipment being used.  
CV and VAV Unit Zone  
Sensor Options  
Integrated ComfortSystems Sensors for CV and VAV  
Applications  
These zone sensor options are for use with cooling/heating Integrated Comfort System  
(ICSTM) systems.  
BAYSENS014 Description  
This electronic analog sensor features single setpoint capability and timed override  
with override cancellation.  
BAYSENS014 features and system control functions include:  
Remote temperature sensing in the zone  
A timed override button to move an ICSTM or a building management system from its  
unoccupiedto occupiedmode.  
Figure I-PR-19. BAYSENS014  
Zone temperature sensor w/timed override  
and local setpoint adjustment,  
Thumbwheel for local setpoint adjustment  
A cancel button to cancel the unoccupied overridecommand.  
Accessory Model Number Digit 6 = C  
BAYSENS013 Description  
This electronic analog sensor features single setpoint capability and timed override  
with override cancellation. It is used with aTrane Integrated ComfortTM system.  
BAYSENS013 features and system control functions include:  
Remote temperature sensing in the zone  
A timed override button to move an ICSor a building management system from its  
unoccupiedto occupiedmode.  
Cancel button to cancel the unoccupied overridemode.  
Figure I-PR-20. BAYSENS013  
Zone temperature sensor w/timed override ,  
Accessory Model Number Digit 6 = B  
52  
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Pre-Startup  
Requirements  
Installation  
Zone Sensor Installation  
All sensor options ship in the main control  
panel and are field-installed.  
Programmable option installation  
procedures are on page 55.  
Note: Guidelines for wire sizes and  
lengths are shown in Table I-PR-7. The total  
resistance of these low voltage wires  
must not exceed 2.5 ohms per conductor.  
Any resistance greater than 2.5 ohms may  
cause the control to malfunction due to  
excessive voltage drop.  
Mounting Location  
Mount the sensor on the wall in an area  
with good air circulation at an average  
temperature. Avoid mounting space  
temperature sensor is areas subject to  
the following conditions:  
Note: Do not run low-voltage control  
wiring in same conduit with high-voltage  
power wiring.  
Drafts or deadspots behind doors or  
in corners  
Hot or cold air from ducts  
Figure I-PR-21. Standard zone sensor,  
BAYSENS017, ships with all units.  
Radiant heat from the sun or appliances  
Concealed pipes and chimneys  
Unheated or non-cooled surfaces  
behind the sensor, such as outside walls  
Airflows from adjacent zones or other  
units  
1. Run wires between the unit control  
panel and the zone sensor subbase.To  
determine the number of wires  
required, refer to the unit wiring  
diagrams.  
2. Connect the wiring to the appropriate  
terminals at the unit control panel and  
at the zone sensor subbase. In general,  
zone sensor connections to the unit use  
the convention of connecting zone  
sensor terminals to like numbered unit  
terminals (1 to 1, 2 to 2, etc.). The  
connection detail is shown on the unit  
wiring diagrams, which are located in  
the unit control panel.  
To mount the sensors, remove the dust  
cover and mount the base on a flat  
surface or 2" x 4" junction box. Sensors  
ship with mounting screws.  
Mounting the Subbase  
Remove the zone sensor cover from  
subbase, and mount subbase on the wall  
or on a 2 x 4 junction box. Route wires  
through the wire access hole in the  
subbase. See Figure I-PR-22 on page 54.  
Seal the hole in the wall behind the  
subbase.  
3. Replace the zone sensor cover back  
on the subbase and snap securely into  
place.  
Wiring  
Standard Remote Sensor  
(BAYSENS017)  
When using the remote sensor,  
BAYSENS017, mount it in the space that  
is to be controlled. Wire according to the  
interconnecting wiring diagrams on the  
unit.  
ƽ WARNING  
!
Disconnect all electric power  
including remote disconnects  
before servicing. Failure to do so  
before servicing may cause severe  
personal injury or death.  
Table I-PR-7. Zone Sensor Maximum  
Lengths and Wire Size  
Distance from  
Unit to Controller  
0-150 feet  
Recommended  
Wiring Size  
22gauge  
151--240 feet  
241-385 feet  
386- 610 feet  
611-970 feet  
20gauge  
18gauge  
16gauge  
14gauge  
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Pre-Startup  
Requirements  
Installation  
Figure I-PR-22. Zone sensor mounting hole locations.  
Mounting Directly to the Wall  
Mounting to Junction Box  
Junction  
Figure I-PR-23. Typical zone sensor installation.  
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Pre-Startup  
Requirements  
Installation  
Programmable Night Setback  
Zone Sensors  
Programmable night setback (NSB) zone  
sensors provide programming and zone  
temperature sensing for the self-  
contained unit. It allows the user to  
monitor room temperatures and  
program settings in the space, without  
having to access the unit control panel.  
ConstantVolume Zone Sensor  
Variable AirVolume Zone Sensor  
BAYSENS019 Description  
BAYSENS020B Description  
This seven day programmable sensor  
with night setback has four periods for  
occupied\unoccupied programming per  
day. If power is interrupted, the program  
retains in permanent memory. If power is  
off longer than 2 hours, only the clock and  
day may have to be reset.  
This seven day programmable sensor  
with night setback has four periods for  
occupied\unoccupied programming per  
day. Either one or all four periods can be  
programmed. If power is interrupted, the  
program retains in permanent memory. If  
power is off longer than 2 hours, only the  
clock and day may have to be reset.  
Reference programming instructions for  
these zone sensors on page 64.  
The six programming keys on the front of  
the zone sensor allow selection of system  
modes (heat, cool, auto, and off), two fan  
modes (on and auto). The zone sensor  
has dual temperature selection with  
programmable start time capability.  
The occupied cooling setpoint ranges  
between 40 and 80 F.The warmup  
setpoint ranges are between 50 and 90 F  
with a 2 degree deadband. The  
The zone sensor keypad allows you to  
select occupied/unoccupied periods with  
two temperature inputs (cooling supply  
air temperature and heating warmup  
temperature) per occupied period. The  
occupied cooling setpoint ranges be-  
tween 40 and 80 F.The warmup setpoint  
ranges between 50 and 90 F with a 2  
degree deadband. The unoccupied  
cooling setpoint ranges between 45 and  
98 F.The heating setpoint ranges be-  
tween 43 and 96 F.  
unoccupied cooling setpoint ranges  
between 45 and 98 F.The heating  
setpoint ranges between 43 and 96 F.  
Two liquid crystal displays (LCD) display  
zone temperature, setpoints, week day,  
time, and operational mode symbols.  
The liquid crystal display (LCD) displays  
zone temperature, setpoints, week day,  
time, and operational mode symbols.  
The DIP switches on the subbase enable  
or disable applicable functions; i.e.  
morning warmup, economizer minimum  
CFM override during unoccupied status,  
Fahrenheit or Centigrade, supply air  
tempering, remote zone temperature  
sensor, 12/24 hour time display, smart  
fan, and computed recovery.  
The DIP switches on the subbase enable  
or disable applicable functions; i.e.  
morning warmup, economizer minimum  
position override during unoccupied  
status, heat installed, remote zone  
temperature sensor, 12/24 hour time  
display, and daytime warmup. During an  
occupied period, an auxiliary relay rated  
for 1.25 amps @ 30 volts AC with one set  
of single pole double throw contacts  
activates.  
During an occupied period, an auxiliary  
relay rated for 1.25 amps @ 30 volts AC  
with one set of single pole double throw  
contacts activates.  
Figure I-PR-24. BAYSENS019, Programmable  
night setback sensor, Accessory Model  
Number Digit 6 = G  
Figure I-PR-25. BAYSENS020, Programmable  
night-setback sensor,  
Accessory Model Number Digit 6 = J  
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Pre-Startup  
Requirements  
Installation  
Programmable Night Setback  
Zone Sensor Installation  
See Figure I-PR-27.To remove the zone  
sensor module from the subbase,  
gently pull away and upward.  
6. Pull the zone sensor module wires  
through the subbase as shown in Figure  
I-PR-31.  
7. Loosely secure subbase to the wall  
with the mounting screws. Do not  
tighten the subbase screws yet.  
8. Level the subbase by sight, then firmly  
tighten the three subbase mounting  
screws.  
Mounting Location  
Mount the sensor on the wall in an area  
with good air circulation at an average  
temperature. Choose a location that is  
easily accessible, and on a wall where the  
subbase can be mounted about 5 feet  
(1.5 meters) above the floor.  
ƽ CAUTION  
!
The zone sensor module is an  
electronic sensitive device. Do  
not touch printed circuit board,  
electronic components, or  
connector pins. Handle plastic  
housing only to prevent damage  
to electronic components.  
Avoid mounting space temperature  
sensor is areas subject to the following  
conditions:  
Drafts or deadspots behind doors or  
in corners  
Hot or cold air from ducts  
Radiant heat from the sun or appliances  
Concealed pipes and chimneys  
Unheated or non-cooled surfaces  
behind the sensor, such as outside walls  
Airflows from adjacent zones or other  
units  
Figure I-PR-28. Removing the zone sensor  
module from the subbase.  
Figure I-PR-29. Securing the subbase.  
(95 mm)  
2. After disassembly, protect the internal  
surfaces from contact with objects or  
substances that could cause damage.  
3. Remove the terminal block from  
subbase and set aside for wiring.  
Discard the tape.  
4. Mount the zone sensor module using  
the mounting hardware included in the  
shipping package. The mounting  
hardware is contained in single plastic  
bag and includes:  
ƽ CAUTION  
!
Do not overtighten the subbase  
screws. Overtightening may  
cause the screws to crack the  
subbase.  
(140 mm)  
Figure I-PR-26. BAYSENS019 dimensions.  
9. Before wiring the subbase, identify the  
wires from the units low voltage  
terminal strip. Each screw terminal is  
labeled.  
10. Remove TB from subbase and  
discard the tape.  
Plastic wall anchors (3 x)  
Mounting screws (3 x)  
The zone sensor module can mount  
directly to a wall or to a junction box  
mounted to a wall.To mount to a  
junction box, you must have the  
mounting plate and adapter kit,  
BAYMTPL003. Installation instructions  
are enclosed with the mounting plate.  
5.To mount the zone sensor module  
directly to a wall:  
(95mm)  
11. Strip the wires 1/4and connect the  
wires from the units low voltage  
terminal strip to the zone sensor  
module subbase. Reference connection  
details on the unit wiring diagrams,  
located on the unit.  
12. Firmly tighten each screw terminal.  
13. Fit the wires as close to the subbase  
as possible.  
(140mm)  
Figure I-PR-27. BAYSENS020 dimensions.  
a. Hold the subbase in position and mark  
the three mounting hole locations on  
the wall.  
Installation Procedure  
1. Remove the zone sensor module from  
the subbase. Carefully hold the zone  
sensor module with one hand and  
firmly grasp the subbase with the other.  
b. Drill three 3/16(4.8 mm) holes. Gently tap  
the plastic wall anchors into the holes  
until the anchor tops are flush with the  
wall.  
56  
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Pre-Startup  
Requirements  
Installation  
Time Clock Option  
The time clock option has a  
3. Provide a separate independent circuit  
for the time clock  
power supply.  
programmable timer that is factory wired  
to the unoccupied input to provide on/off  
control. The time clock will not allow the  
unit to pass through the night setback/  
morning warmup mode, except on units  
with optional night heat/morning warm  
up, or programmable night setback. See  
Figure I-PR-30.  
4. Since all electronic instruments are  
sensitive to voltage spikes, pay close  
attention to the following:  
a. If possible, supply power to the  
electronic time clock from a phase  
different than the one supplying power  
to the load  
b. Provide a suitableVaristor or RC  
network across the INDUCTIVE LOADS  
supply terminals to reduce voltage  
spikes.  
c. Place a diode across the DC OPERATED  
INDUCTOR terminals to eliminate back  
EMF.  
The timeclock, a Digi 20by Grasslin, is  
inside the control panel, but accessible  
with the control panel door closed. This  
same type timer is also used for pro-  
grammable night setback/morning warm  
up. Programming instructions for the  
Digi 20timer are in the Program-  
mingsection on page 73.  
Figure I-PR-30. Grasslin time clock option.  
d. HIGHLY INDUCTIVE LOADS, especially  
fluorescent lights, may require a relay  
in which case (A) and (C) apply.  
Timeclock Installation  
1. Ensure operating temperature is within  
4 to 131 F.  
The Digi 20A timeclock unit can be  
surface or flush mounted. Lift off the front  
cover and loosen the two screws on  
opposite corners. Pull off the bases plug  
with a left to right rolling motion.  
2. Locate the time clock at least 5 feet  
away from any large electrical contact  
or machinery to avoid possible  
electrical interference problems.  
3. Provide a separate independent circuit  
for the time clock power supply.  
4. Since all electronic instruments are  
sensitive to voltage spikes, pay close  
attention tot he following:  
a. If possible, supply power to the  
electronic time clock from a phase  
different than the one supplying power  
to the load.  
b. Provide a suitableVaristor or RC  
network across the INDUCTIVE  
LOADS supply terminals to reduce  
voltage spikes.  
c. Place a diode across the DC  
OPERATED INDUCTOR terminals to  
eliminate back EMF.  
Surface Mounting Inside Panel  
Place screws through the bases preset  
holes and screw to back of panel or wall.  
Wire according to the instructions in the  
following section. Depending upon the  
specific installation, you may find it more  
convenient to complete wiring before  
attaching the base.  
Place the terminal cover over the  
terminal block by aligning the two screws  
with the corner holes in the base. Push  
the timer firmly onto the plug in the base.  
Tighten the two screws. A base for DIN  
rail mounting is optional.  
Wiring theTimeclock  
d. HIGHLY INDUCTIVE LOADS, especially  
fluorescent lights, may require a relay  
in which case step a. and c. apply.  
1. Wire 24, 120, or 220 VAC to input  
terminals. Make sure to apply correct  
voltage. Using incorrect voltage will  
void the warranty.  
2. Connect wire to the screw terminals  
according to the unit wiring diagrams.  
Use 12 to 22 AWG wire.  
The timeclock can be surface or flush  
mounted. Lift off the front cover and  
loosen the two screws on opposite  
corners. Pull off the bases plug with a left  
to right rolling motion.  
Timeclock Installation Checklist  
1. Ensure operating temperature is within  
4 to 131 F.  
2. Locate the time clock at least 5 feet  
away from any large electrical contact  
or machinery to avoid possible  
electrical interference problems.  
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Pre-Startup  
Requirements  
Installation  
Installing the Remote Human  
Interface Panel  
Human Interface (HI) Panel  
The HI enables the user to communicate  
necessary unit operating parameters and  
receive operating status information  
from within the occupied space.  
The HI displays top level information in  
the LCD window, unless the operator  
initiates other displays, for the various  
unit functions. It also displays menu  
readouts in a clear language 2 line, 40  
character format. The 16-key keypad  
allows the operator to scroll through the  
various menus to set or modify the  
operating parameters. See Figure I-PR-  
31 to reference the HI keypad.  
Remote Human Interface Panel  
The remote human interface (RHI) panel  
is identical to the unit mounted HI with the  
exception of the unit selectkey.This  
key allows the operator to switch from  
one unit to the next to program or view  
status information regarding a particular  
unit.  
The RHI functions the same as the unit  
mounted HI with two exceptions. The first  
is the test startfunction. The operator  
can view the service parameters, but can  
only initiate the service test function at  
the unit. The RHI door has a locking screw  
to deter access by unauthorized person-  
nel. Additionally, the RHI can control up to  
four different units.  
Figure I-PR-31. Human Interface (HI) Panel Keypad  
HI Location Recommendations  
The HI microprocessor module is  
mounted inside a molded plastic  
enclosure for surface mounting. It is not  
weatherproof. Therefore, it is only  
applicable for indoor use.  
Table I-PR-8. Maximum Communication  
Link Wiring Length  
AmbientTemperature and Humidity  
Limits  
Ambient Operating Conditions  
Temperature: 32 to 120 F  
Relative humidity: 10 to 90%, non-  
condensing  
Ambient Storage Conditions  
Temperatures: -50 to 200 F  
Relative humidity: 5 to 95%, non-  
condensing  
Max. Wire  
tance  
Max. Capaci-  
Length  
Between  
Locate the RHI panel in an area that will  
ensure the communication link between  
the panel and the unit(s) does not exceed  
5,000 feet maximum or pass between  
buildings. SeeTable I-PR-8.  
Conductors  
1,000 ft  
2,000 ft  
3,000 ft  
4,000 ft  
5,000 ft  
up to 60 pf/ft  
up to 50 pf/ft  
up to 40 pf/ft  
up to 30 pf/ft  
up to 25 pf/ft  
Note: pf/ft = picofarads/foot  
The run length of the low voltage AC  
power wiring to the remote HI must not  
exceed three (3) ohms/conductor. Refer  
toTable I-PR-9.  
Table I-PR-9. Wiring Recommendations for  
the Remote HI Panel  
Distance from Unit  
to Remote HI  
Recommended  
Wire Size  
0-460 feet  
18 gauge  
16 gauge  
14 gauge  
461-732 feet  
733-1000 feet  
58  
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Pre-Startup  
Requirements  
Installation  
Mounting the Remote Human  
Interface (RHI) Panel  
Note: The top of the enclosure is marked  
“TOP.”  
Note: The top of the enclosure is marked  
with “TOP.”  
The installer must provide all mounting  
hardware such as; hand tools, electrical  
boxes, conduit, screws, etc. Refer to  
Figure I-PR-32 on page 60 for the  
4.With the enclosure in the correct  
position; align the mounting holes  
around the knockout in the enclosure  
with the screw holes in the electrical  
handy box and secure with the  
appropriate screws.  
4. With the enclosure in the correct  
position, remove the enclosure and  
drill the necessary holes in the surface  
for the appropriate fasteners, (plastic  
anchors, molly bolts, screws, etc.)  
mounting hole and knockout locations.  
Procedure  
5. Remove the necessary knockouts for  
the wire or conduit entry before  
mounting the panel.  
Follow the procedure below for  
mounting the remote HI panel on a 4by  
4electrical junction box. Place the  
microprocessor in a clean dry location  
during the enclosure mounting  
procedures to prevent damage.  
5. Replace the microprocessor within the  
enclosure as follows:  
a. Verify that the terminal block jumpers  
are connected properly.  
6. Place the enclosure back onto the  
surface and secure it with the  
appropriate screws.  
b. Slide the extruded hinge pin at the top  
left of the key pad plate into the hole  
located at the top left hand side of the  
enclosure.  
1. Mount an electrical junction box in the  
wall so that the front edge of the box  
will be flush with the finished wall  
surface.  
7. Follow step 5 in the previous section,  
Mounting on a 4by 4Electrical  
Box,to replace the microprocessor  
within the enclosure.  
c. Slide the bottom of the plate into place,  
aligning the two (2) clearance holes  
with the screw holes on the right. Install  
the screws but do not tighten at this  
time.  
2. Prior to mounting the panel, the  
microprocessor module must be  
carefully removed from the enclosure.  
To remove the module:  
a. Lay the remote panel face up on a flat  
surface and remove the locking screw  
from the right hand bottom end of the  
panel.  
Note: If the two screws are not installed as  
called out in the previous step, hold  
against the key pad plate while installing  
the door in the next step, to prevent it from  
falling out.  
b. Remove the recessed hinge screw  
from the left hand bottom end of the  
panel.  
d. Slide the extruded hinge pin at the top  
left of the door into the hole located  
under the bottom left side of the display.  
c. Unlatch the door of the enclosure as if  
to open it, and slide the left hand side of  
the door upward away from the hinge.  
Lay it aside.  
e. Install and tighten the hinge screw  
located at the bottom left side of the  
enclosure.  
d. With the key pad visible, remove the  
two (2) screws located on the right  
hand side of the key pad.  
Wall Mounting the RHI Panel  
1. Prior to mounting the panel, the  
microprocessor module must be  
removed from the enclosure. Complete  
step 2 in the previous discussion,  
Mounting on a 4 in. x 4 in. Electrical  
Box,before proceeding.  
e. Carefully slide the key pad plate  
upward from the bottom, releasing the  
extruded hinge pin from its socket at  
the top.  
2. With the microprocessor removed,  
refer to Figure I-PR-31 for the location of  
the mounting holes to be used for wall  
mounting.  
f. Set the microprocessor aside until  
mounting is complete.  
3. Remove the junction box knockout in  
the back of the enclosure.  
3. Place the enclosure against the  
mounting surface and mark the  
mounting holes.  
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Pre-Startup  
Requirements  
Installation  
Figure I-PR-32. Remote HI mounting holes and knockout locations.  
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Pre-Startup  
Requirements  
Installation  
Wiring the Remote Human  
Interface  
The remote human interface requires 24  
VAC + 4 volts power source and a  
shielded twisted pair communication link  
between the remote panel and the  
interprocessor communication bridge  
(ICPB) module at the self-contained unit.  
Communication Link (ShieldedTwisted  
Pair) Wiring  
Connect the wire connected to the  
positive (+) terminal at the remote panel.  
Connect the wire connected to the  
negative (-) terminal at the remote panel.  
Connect the ground wire from the  
remote panel to the unit control panel  
casing.  
Trim the outer covering of the shielded  
cable back approximately 1 inch. See  
Figure I-PR-35. Do not cut the bare  
shield wire off. Strip approximately 1/2  
inch of insulation from each insulated  
wire to connect them to the terminal strip  
at the remote panel.  
Interprocessor Communication Bridge  
Module Wiring  
Field wiring for both the low voltage  
power and the shielded twisted pair must  
meet the following requirements:  
Connect the white lead to the positive (+)  
terminal, the black lead to the negative (-)  
terminal, and the bare shield wire to the  
terminal at the remote human interface  
panel.  
Refer to Figure I-PR-33 and trim the outer  
covering of the shielded cable back  
approximately one inch. Cut the bare  
shield wire off even with the outer  
covering. Strip approximately 1/2 inch of  
insulation from each insulated wire in  
order to connect them to the terminal  
strip at the unit. Wrap tape around any  
exposed foil shield and/or base shield  
wire.  
Note: To prevent control malfunctions, do  
not run low voltage wiring (30 volts or less)  
in conduit with higher voltage circuits.  
Close the key pad plate. Install and  
tighten the two screws removed earlier.  
Close the outer door and install the  
recessed locking screw at the bottom  
right hand side of the enclosure to  
prevent accidental starting of the unit by  
unauthorized personnel while completing  
the wiring at the self-contained unit.  
1. All wiring must be in accordance with  
NEC and local codes.  
Note: The communication link is polarity  
sensitive.  
2. ReferenceTable I-PR-8 on page 58 for  
recommended wiring distance and size.  
At the Self-Contained Unit  
Refer to the unit wiring diagram and  
connect the white lead to the positive (+)  
terminal and the black lead to the  
negative (-) terminal. (These terminals  
are numbered. Reference to color is for  
clarification to maintain polarity).  
Connect the opposite end of the three  
conductor 24 volt wire to the appropriate  
terminal strip as follows:  
3. Communication link wiring must be 18  
AWG shielded twisted pair (Belden  
8760, or equivalent).  
Note: Although the 24 volt power is not  
polarity sensitive, do not connect either  
the + (plus) or - (minus) terminals from the  
remote panel to ground at the self-  
contained unit.  
4. Communication link must not exceed  
5,000 feet maximum for each link.  
Note: To maintain polarity, do not connect  
the base shield wire to ground at the self-  
contained unit.  
5. Do not run communication link  
between buildings.  
ƽ WARNING  
!
Before servicing unit, disconnect  
all electric power, including  
remote disconnects. Failure to do  
so may cause severe personal  
injury or death.  
Low Voltage (AC) Field Wiring  
Connections  
To access the wire entry locations, open  
the RHI panel door and remove the two  
screws on the right-hand side of the key  
pad. Swing the keypad open, exposing  
both the wire entries and the back of the  
HI module. Refer to Figure I-PR-32 on  
page 60 and connect one end of the three  
conductor 24 volt wires to the remote  
panel terminal strip (+), (-), and (ground).  
Figure I-PR-33. Dressing shielded twisted wire.  
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Pre-Startup  
Requirements  
Installation  
Connecting to Tracer Summit®  
Communication Wiring  
IntelliPak® self-contained units operate  
withTrane building automation software,  
Tracer Summit® version 10.0.4 or later or  
any OS2 operating system.  
Note: Communication link wiring is a  
shielded, twisted pair of wire and must  
comply with applicable electrical codes.  
An optional communication link provides  
a serial communication interface (SCI)  
betweenTracer Summit® and each  
commercial self-contained (CSC) unit in  
the system. The CSC system can have a  
maximum of 12 CSC units per connection  
link to Summit®. Use a single 18 AWG  
shielded, twisted pair wire with stranded,  
thinned copper conductors to establish  
each communication link between  
Summit® and each unit.  
ƽ CAUTION  
!
Tape the non-insulated end of the  
shield on shielded wire at the  
unit. Any connection between the  
shield and ground will cause a  
malfunction. If daisy-chained in  
the unit, splice and tape the  
shields to prevent contact with  
ground.  
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Pre-Startup  
Requirements  
Installation  
oCheck the belt tension for proper  
adjustment.  
oEnsure the fan rotates freely.  
oTighten locking screws, bearing set  
screws and sheaves.  
oEnsure bearing locking collars do not  
wobble when rotated.  
Pre-Startup Checklist  
Complete this checklist after installing the  
unit to verify all recommended  
installation procedures are complete  
before unit start-up. This does not replace  
the detailed instructions in the  
appropriate sections of this manual.  
Always read the entire section carefully  
to become familiar with the procedures.  
Ductwork  
oIf using return ductwork to the unit,  
secure it with three inches of flexible  
duct connector.  
ƽ WARNING  
!
Disconnect electrical power to  
prevent injury or death from  
electrical shock.  
oExtend discharge duct upward without  
change in size or direction for at least  
three fan diameters.  
oUse a 3flexible duct connection on  
discharge ductwork.  
oEnsure trunk ductwork toVAV boxes is  
complete and secure to prevent leaks.  
oVerify that all ductwork conforms to  
NFPA 90A or 90B and all applicable  
local codes  
Receiving  
oInspect unit and components for  
shipping damage. File damage claims  
immediately with the delivering carrier.  
oCheck unit for missing material. Look  
for ship-with drives, isolators, filters,  
and sensors that are packaged  
separately and placed inside the main  
control panel, fan section, or  
Water-Cooled Unit Piping  
oVerify the condensate drain piping is  
complete for the unit drain pan. Install  
and tighten the condensate Ptrap  
drain plug.  
compressor section. See page 9 for  
more information on ship-with items.  
oCheck nameplate unit data to verify  
against the sales order requirements.  
oInstall water piping drain plugs,  
economizer header, and condenser  
vent plugs.  
oMake return and supply water  
connections to the unit and/or  
waterside economizer piping package  
with recommended valves and piping  
components. Refer to the Water  
Pipingsection on page 34.  
oInstall unions to allow waterside  
maintenance.  
oInstall cooling tower and standby  
pumps.  
oTreat water to prevent algae, slime,  
and corrosion.  
Unit Location  
oRemove crating from the unit. Do not  
remove the shipping skid until the unit is  
set in its final position.  
oEnsure the unit location is adequate for  
unit dimensions, ductwork, piping, and  
electrical connections.  
oEnsure access and maintenance  
clearances around the unit are  
adequate. Allow space at the end of the  
unit for shaft removal and servicing.  
See the Service Accesssection on  
page 11.  
oPrevent refrigerant piping from  
rubbing against other objects.  
Unit Mounting  
Air-Cooled Units Only  
oConnect refrigerant lines.  
oInstall liquid line filter driers.  
oPlace unit in its final location.  
oRemove shipping skid bolts and skid.  
oIf using isolators, properly mount using  
the isolator placement sheet.  
oRemove shipping brackets on the  
compressors and supply fan.  
oRemove the unit protective shipping  
covers.  
Units with Hydronic Heat  
oVerify the entering water temperature  
sensor is installed upstream of the  
hydronic coil.  
Units with Electric Heat  
oVerify the supply air temperature  
sensor is installed downstream of the  
electric heat coil.  
Component Overview  
oVerify the fan and motor shafts are  
parallel.  
oVerify the fan and motor sheaves are  
aligned.  
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Installation  
Programming  
Programmable Zone Sensor  
Option  
BAYSENS019  
Figure I-P-1. BAYSENS019 Keypad and display configuration.  
BAYSENS019 Keypad and Display  
Explanation  
4. Erase Button  
8. Mode Button  
Erases time and temperature settings  
throughout each of the programmed  
periods.  
Toggles the controller through its four  
modes: off, heat, cool, and auto; if HP  
version, also emer (emergency).  
1. Up and Down Buttons  
Increases or decreased programmed  
temperature settings in program menu.  
Shifts to temporary manual override in  
normal run mode.  
Exits temporary manual override.  
9.  
5. Day Button  
Toggles through the seven days of the  
week.  
Indicates day of the week  
Indicates begin time in program menu  
Indicates time setting in temporary  
override mode.  
Increases or decreases temperature  
while in temporary override menu.  
6. HoldTemp Button  
2.Time Adjust Button  
Shifts controller to temporary manual  
override, and begins temperature  
override.  
Used to set the correct time of day. Used  
to set programmed time for temperature  
variations.  
7. Fan Button  
Toggles the fan controller between on  
and auto mode.  
3. Program Button  
Toggles between the display control  
screen and the display program screen.  
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Installation  
Programming  
BAYSENS020  
Figure I-P-2. BAYSENS020 Keypad and display configuration.  
BAYSENS020 Keypad and Display  
Explanation  
3. Program Button  
Toggles between the display control  
screen and the display program screen.  
7. Mode Button  
Toggles the controller between the two  
modes, off and auto.  
Advances to next setpoint in program  
menu.  
1. Up and Down Buttons  
Increases or decreased programmed  
temperature settings in program menu.  
Shifts to temporary manual override in  
normal run mode.  
4. Erase Button  
Erases time and temperature settings  
throughout each of the programmed  
periods.  
8. During Programming Indicates:  
Heat supply air  
Cool supply air  
Warmup temperature  
Increases or decreases temperature  
while in temporary override menu.  
Pressed together, toggles between  
unoccupied/occupied setting.  
Exits temporary manual override.  
5. Day Button  
Toggles through the seven days of the  
week.  
2.Time Adjust Button  
6. HoldTemp Button  
Used to set the correct time of day. Used  
to set programmed time for temperature  
variations.  
Shifts controller to temporary manual  
override, and begins temperature  
override.  
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Installation  
Programming  
Initial Power-Up  
to the program menu. See Figure I-P-2.  
Before toggling to the program menu,  
use the mode button to select the type  
setpoints to review or program (heat,  
cool or auto). For example, if you select  
cool mode before toggling to the program  
menu, then only the cool setpoints are  
reviewed or programmed. If you select  
heat mode, then only the heat setpoints  
are reviewed or programmed. In auto  
mode, both heat and cool setpoints are  
reviewed and programmed.  
While in program menu, each time you  
press and release the program button,  
the ZSM toggles through the four  
periods that divide each day.Those four  
periods are: Morn(ing), Day, Eve(ning),  
and Night.  
During unoccupied periods, only the  
desired room temperature setpoints are  
entered. Each unoccupied period has a  
heat and cool setpoint, and both setpoints  
are offered during programming.  
Before applying power to your ZSM, and  
before performing setup and operation  
procedures, verify that all wiring is  
correct. See Figures I-P-9 on page 71 and  
I-P-10 on page 72 for a complete zone  
sensor icon display description.  
Blank temperature settings may also be  
entered. When a setpoint is blank, the  
program will default to the last setpoint of  
its type. If there is no setpoint of its type,  
the default setpoint is used. If all setpoints  
in the time period are blank, is erased  
after exiting from the program menu.  
For BAYSENS020 only: at initial power-  
up, the ZSM controls to default tempera-  
tures of 68 F (19 C) for warmup, and 55 F  
(13 C) supply air, until the ZSM is pro-  
grammed or the arrow keys are pressed.  
If the arrow keys and mode are moved,  
the ZSM starts controlling to these new  
settings.  
The ZSM has independent, seven day  
programming:  
Each day can be programmed with  
different times, temperatures, and  
occupied status.  
Each day can be programmed with up  
to four periods. Although four periods  
are available each day, you can  
program just one of the four.  
Each period can be programmed for  
occupied or unoccupied.  
Time and Day Settings  
On power-up your ZSM will be in normal  
run mode and will begin operating using  
setpoints. The display will show the  
wrong day and time and will need to be  
set.  
To exit the program menu, depress the  
program button for two seconds.  
To set the time, there is a single rubber  
button on the keypad minusand  
plusmark time.  
To begin programming, follow these  
steps:  
Depressing the positive side will advance  
the time. Depressing the negative side  
will decrease the time.  
Determine which periods during the day  
will be occupied and unoccupied.  
Each time you depress the positive or  
negative side minusand plus, the  
time will either advance or decrease  
respectively by one minute. If you press  
and hold either side of the time button,  
the time change will accelerate rapidly.  
Write your daily schedule on the sheet  
enclosed with the zone sensor.  
Enter your program by following the  
steps below.  
To program time periods and setpoints  
for a day:  
Press the program button to enter  
program mode.  
Press the day button to select first day to  
be programmed.  
To set the begintime for the first  
period of the day, press the minus or  
plus keys.  
Figure I-P-3. Display Program Menu Screen.  
When you reach the correct time, release  
the time button and the time will be set  
into permanent memory.  
Program Menu  
BAYSENS020 Only  
Note: To ensure the time changes are  
made, the ZSM will initiate a 30 second  
user-stabilization time before making  
changes to the ZSM operation mode.  
Note: After toggling to the program  
screen, the week is divided into seven  
days with each day divided into four  
periods.  
To set the temperature setpoint for that  
period, use - or ¯ꢀ  
Setpoint programming depends on the  
setting status, occupied or unoccupied,  
and whether or not the heat installed,  
modulated heat, morning warmup, or  
daytime warmup options are enabled.  
Press the program button to move to  
the next period for that day.  
To program time periods and setpoints  
for the next day, press the day button.  
When finished, press and hold the  
program button for two seconds to  
return to the normal run mode.  
Keypad Operation  
Note: After toggling to the program  
screen, the week is divided into seven  
days with each day divided into four  
periods. Therefore, 28 program settings  
are possible.  
In the occupied period, the cool supply air  
temperature is always set. If heat  
installed and modulated heat options are  
on, the supply air heat is also set during  
occupied periods. The warmup tempera-  
ture is also set in occupied periods, if heat  
installed and warmup options are  
enabled.  
Program Button  
Depressing the program button will  
toggle the display from normal run mode  
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Installation  
Programming  
Note: Blank temperature settings may be  
entered at any of the four daily periods.  
When a setpoint is left blank and in an  
occupied condition, the ZSM will default to  
the last occupied setpoint. When a  
setpoint is left blank and in an unoccupied  
condition, the ZSM will default to the last  
unoccupied setpoint.  
Keypad lockout applies only to normal  
run mode and temporary manual  
override mode.  
a temporary manual override menu. See  
Figure I-P-3.  
This mode overrides any number of  
programmed setpoints through any of  
the 28 programmed periods. After  
entering setpoints and length of override  
time, these settings are now used.  
Day Button  
In normal run mode, depressing the day  
button will move the current day ahead.  
While in the program menu, depressing  
the day button will move you through  
the seven days of the week and allow  
you to program temperature settings  
for each of the four daily periods.  
Temporary Manual Override  
While in normal run mode, depressing  
the hold temp button toggles the ZSM to  
the temporary manual override menu.  
Erase Button  
Pressing the erase button while in  
normal run mode will turn off the check  
filter icon.  
The mode will override any number of  
programmed setpoints through any of  
the 28 programmed periods. After  
entering setpoints and length of override  
time, these new settings are used in place  
of the setpoints programmed for normal  
run mode.  
Pressing the erase button while in the  
program menu, will erase all time and  
temperature setpoints of a given  
period.  
The erase button will acknowledge the  
failure buzzer (Option 16) until 12:00 am.  
Figure I-P-4. Temporary Manual Override  
Menu Screen.  
Time Button  
Mode Button  
While in the program menu, each time  
you press and release the positive or  
negative side of the time button, the  
time will advance or decrease by ten  
minute increments. If you press and  
hold the positive or negative side  
(minusand pluskeys), the ZSM  
will increment rapidly.  
Keypad Operation for Temporary Manual  
Override Menu  
BAYSENS019 only: Pressing the mode  
button toggles through all modes: off,  
heat, cool, auto, and emer (HP unit).  
BAYSENS020 only: Pressing the mode  
button while in normal run mode, or  
temporary manual override run mode,  
will toggle through both modes, off and  
auto.  
The keypad has the same function in  
temporary manual override menu as in  
all other menus, with a few exceptions:  
Depressing the day button will toggle  
your ZSM between the day and hour  
icon. See Figure I-P-3 on page 65.  
Depressing the mode button will toggle  
your ZSM between the heat and cool  
icons and setpoints.  
Depressing the erase button will cancel  
the override and return the ZSM to  
normal run mode.  
Depressing the holdtemp or program  
buttons while in the temporary manual  
override menu will toggle your ZSM to  
the temporary override mode. See  
Figure I-P-4.  
When the display is in the normal run  
mode, each time you press and release  
the positive or negative side of the time  
button (minusand pluskeys), the  
time will advance or decrease by one  
minute. If you press and hold the  
positive or negative side (minusand  
pluskeys), the ZSM will increment  
rapidly.  
Fan Button  
The fan button allows you to toggle  
between on and auto.  
Up and Down Button Arrows  
Depressing - or ¯ arrow while in normal  
run mode will cause your ZSM to toggle  
to the temporary manual override  
menu.  
Depressing either - or ¯ arrow while in  
the program menu or temporary  
override menu will cause the  
temperature setpoint to advance or  
decrease in one degree increments.  
Depressing and holding either the - or ¯  
arrow will cause the temperature  
setting to increment rapidly.  
Note: Blank temperature settings may be  
entered at any of the four daily periods.  
When a setpoint is left blank and in an  
occupied condition, the ZSM will default to  
the last occupied setpoint.  
Keypad Lockout  
If you simultaneously depress and hold  
both the positive and negative sides of  
the minusand pluskeys for four  
seconds, the lock icon will appear and all  
keypad functions will lock out. If you  
repeat this operation, the lock icon will  
disappear and all keypad functions will be  
available again.  
Simultaneously depressing the - or ¯  
arrow for two seconds while in the  
program menu or temporary override  
menu will toggle the ZSM between an  
occupied and unoccupied condition.  
Holdtemp Button  
While in normal run mode, depressing  
the hold temp button toggles the ZSM to  
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Installation  
Programming  
Keypad Operation for Temporary Manual  
Override Menu  
In temporary manual override run mode,  
most of the keypad functions lock out with  
these exceptions:  
The mode button still functions as in  
normal run mode.  
Depressing the holdtemp button toggles  
the ZSM between temporary manual  
override menu and temporary manual  
override run mode. If no button is  
pressed for 20 seconds, while in the  
temporary manual override menu, the  
ZSM exits to the normal run mode,  
ignoring the temporary manual  
override settings.  
The keypad has the same function in  
temporary manual override menu as in  
all other menus, with a few exceptions:  
Depressing the holdtemp or program  
buttons while in temporary manual  
override menu will enter settings and  
begin temporary manual override run  
mode. See Figure I-P-5.  
Figure I-P-5. Override run mode screen.  
Temporary Override Run Mode  
Depressing either the up or down arrow  
keys while in temporary manual  
override run mode will cause the ZSM  
to toggle to temporary manual override  
menu.  
The temporary override run mode sends  
setpoint data to the Unit Control Module  
(UCM) from the setpoint data entered in  
the temporary manual override menu.  
The erase button will turn off the check  
filter icon if displayed.  
In temporary override run mode, most of  
the keypad functions lock out with these  
exceptions:  
The mode button still functions as in  
normal run mode.  
The fan button still functions as in  
normal run mode.  
Figure I-P-6. Temporary manual override  
menu screen.  
Simultaneously depressing and holding  
the positive and negative sides of the  
minus/plus key for four seconds will lock  
out the keypad.  
Depressing the day button will toggle  
the ZSM between the day and hour  
icon.  
Depressing the mode button will toggle  
the ZSM between the heat and cool  
icons and setpoints.  
Depressing the erase button will cancel  
the override and return the ZSM to  
normal run mode.  
If no button is pressed for 20 seconds,  
the ZSM exits temporary manual  
override menu and enters the normal  
run mode, ignoring the temporary  
manual override menu settings.  
Time is not adjustable in this mode.  
Depressing the holdtemp button toggles  
the ZSM between the temporary  
manual override menu and override  
run mode. (if no button is pressed for 20  
seconds while in temporary manual  
override menu, the ZSM exits to normal  
run mode, ignoring the temporary  
override settings.)  
Depressing either the - or ¯ arrow while  
in the override run mode will cause the  
ZSM to toggle to the temporary manual  
override menu.  
The erase button will turn off the check  
filter icon if displayed.  
Simultaneously depressing and holding  
the positive and negative sides of the  
minusand plusfor four seconds  
will lock out the keypad.  
Figure I-P-7. Temporary manual override run  
mode screen.  
Temporary Manual Override Run Mode  
The temporary manual override run  
mode sends setpoint data to the UCM  
from the setpoint data entered in the  
temporary manual override menu. See  
Figure I-P-7.  
Time is not adjustable in this mode.  
The program button is disabled.  
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Installation  
Programming  
Option Menu and Keypad Operation  
The operation menu sets all  
programmable options built into your  
ZSM. All options are retained in  
permanent EEPROM memory.  
Table I-P-1. Zone Sensor BAYSENS019 Option Menu Settings.  
Option #  
1
Description  
Morning Warmup  
Value  
Factory Setting  
0
0 = Disabled  
1 = Enabled  
2
3
4
5
6
Economizer minimum  
Position override  
0 = Disabled  
1 = Enabled  
0 = Fahrenheit  
1 = Enabled  
0 = Disabled  
1 = Enabled  
0 = 12 hours  
1 = 24 hours  
1
0
0
0
1
0
0
To access the option menu display,  
simultaneously depress and hold the  
mode button and program button for four  
seconds. See Figure I-P-8.  
Temperature Scale  
Supply AirTempering  
Time Clock  
The example in Figure I-P-8 shows option  
15 displayed and indicates the initial timer  
setting in the temporary override run  
mode. The option value shown is in  
Smart Fan  
0 = Disabled  
1 = Enabled  
7
8
IntelligentTemperature Recovery  
Programmable Days/Week  
0 = Disabled  
1 = Enabled  
0 = 7 days (M,T,W,T,F,S,S)  
1 = 3 days (M-F, S, S)  
2 = 2 days (M-F, S,S)  
hours, and value selected is five hours.  
When the option menu displays, the only  
active buttons are the - or ¯ arrow and  
the minusand plusbutton. The - or  
¯ arrow increment through the available  
options by number (1-24), and the  
minusand plusbutton toggles  
through the various option values  
associated with each option number. See  
Table I-P-1.  
9
10  
Programmable Periods/Day  
Programmable Fan Operation  
2,3,4  
4
0
0 = Disallowed  
1 = Allowed  
11  
12  
Remote Sensor Installed  
Check Filter Interval  
0 = No  
1 =Yes  
0 = Disabled  
3000 to 50 in 50 hour  
increments  
0
350  
13  
14  
15  
16  
Display ZoneTemperature  
Keypad Lockout Enabled  
0 = No  
1 =Yes  
0 = Disabled  
1 = Enabled  
1
1
3
1
Note: On both programmable zone sensor  
options, changing either option 9 or 10 will  
erase the current program. To avoid  
reprogramming, set options 9 and 10  
before programming.  
InitialTime Setting inTemporary  
Override Mode (hrs.)  
1,2,3,4,5  
Buzzer Options  
0 = Key Press only  
1 = Key Press & Check filter  
2 = Key Press, Check Filter,  
and System Failures  
17  
18  
ZoneTemperature Calibration  
Baud Rate  
Displays current temp.  
with any offsets  
0 = 1024 baud  
0 offset  
1
1 = 1200 baud  
19  
CV or HP Operation  
0 = CV  
1 = HP  
0
20  
21  
22  
23  
Default Cooling setpoint  
Default Heating setpoint  
Minimum Cooling Setpoint  
Maximum Heating Setpoint  
45 to 98 F  
43 to 96 F  
45 to 98 F  
43 to 96 F  
74 F  
68 F  
45 F  
96 F  
Figure I-P-8. Typical option menu screen.  
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Installation  
Programming  
Note: On both programmable zone sensor  
options, changing either option 9 or 10 will  
erase the current program. To avoid  
reprogramming, set options 9 and 10  
before programming.  
Table I-P-2. Zone Sensor BAYSENS020 Option Menu Settings.  
Option #  
1
Description  
Morning Warmup  
Value  
Factory Setting  
0
0 = Disabled  
1 = Enabled  
2
3
4
5
6
7
8
Economizer minimum  
Position override  
Temperature Scale  
0 = Disabled  
1 = Enabled  
0 = Fahrenheit  
1 = Enabled  
0 = No  
1 =Yes  
0 = 12 hours  
1 = 24 hours  
0 = No  
1 =Yes  
0 = Disabled  
1 = Enabled  
1
0
0
0
0
0
0
Intelligent Copy  
Heat Installed  
Note: Once you have used Intelligent  
Copy, you cannot use it again until you  
ERASE all weekday and weekend time  
periods by pressing ERASE for 5 seconds.  
Time Clock  
Hydronic Heat  
Daytime Warmup  
Programmable Days/Week  
If your heating and cooling requirements  
are the same for each day of the week,  
and for each day of the weekend, your  
ZSM is designed to employ Intelligent  
Copy.  
0 = 7 days (M,T,W,T,F,S,S)  
1 = 3 days (M-F, S, S)  
2 = 2 days (M-F, S,S)  
9
10  
Programmable Periods/Day  
Remote Sensor Installed  
2,3,4  
4
0
0 = No  
1 =Yes  
11  
Check Filter Interval  
0 = Disabled  
3000 to 50 in 50 hour  
increments  
350  
To program the five weekdays, Monday  
through Friday, program only one  
weekday. Likewise, to program the  
weekend, Saturday and Sunday, pro-  
gram only one day. After programming  
one weekday and/or one weekend day,  
Intelligent Copy automatically copies your  
program to the other days.  
12  
13  
Display ZoneTemperature  
Keypad Lockout Enabled  
0 = No  
1 =Yes  
0 = Disabled  
1 = Enabled  
1
1
3
1
14  
15  
InitialTime Setting inTemporary  
Override Mode (hrs.)  
1,2,3,4,5  
Buzzer Options  
0 = Key Press only  
1 = Key Press & Check filter  
2 = Key Press, Check Filter,  
and System Failures  
Using Intelligent Copy:  
1) Be sure to select the seven day  
programming format in the Options  
Menu. SeeTables I-P-1 and I-P-2.  
2) Be sure the entire program is blank.  
3) Go to the program menu.  
16  
ZoneTemperature Calibration  
Displays current temp.  
with any offsets  
45 to 98 F (unoccupied)  
43 to 96 F (unoccupied)  
40 to 80 F (occupied)  
60 to 160 F  
50 to 90 F (occupied)  
45 to 98 F  
43 to 96 F  
40 to 80 F (occupied)  
60 to 160 F  
0 offset  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
Default Cooling Setpoint  
Default Heating Setpoint  
Default Supply Air Cool  
Default Supply Air Heat  
Default Warmup  
Minimum Cooling Setpoint  
Maximum Heating Setpoint  
Minimum Supply Air Cool  
Maximum Supply Air Heat  
Maximum Warmup  
74 F  
68 F  
55 F  
100 F  
68  
45 F  
96 F  
40 F  
160 F  
90 F  
4) Enter your setpoint parameters.  
Intelligent Copy will automatically copy  
these parameters to the other  
weekdays.  
5) Depress the DAY pushbutton until a  
weekend day icon appears.  
50 to 90 F  
6) Enter setpoint parameters. Intelligent  
Copy will automatically copy these  
parameters to the other weekend day.  
Remote Panel Indicator Signals From  
UCM to ZSM  
Table I-P-3. UCM Signal Conditions.  
The unit control module (UCM) can send  
four signals to the ZSM.  
Signal  
On  
Condition  
Heat  
Cool  
On  
FlashingHEAT is ON and indicated by a solid HEAT icon in the  
Display. Failure in the cooling system indicated by a flashing COOL  
FAIL icon.  
FlashingCOOLING is ON and indicated by a solid COOL icon in the  
Display. Failure in the cooling system indicated by a flashing  
COOL FAIL icon.  
FlashingSystem is OFF and indicated by a solid colon on the time of  
day display. System is ON and indicated by a flashing colon on  
the time of day display. System is in TEST mode and indicated by a  
flashing TEST icon.  
ON System requires service and is indicated by a solid SERVICE  
icon.There is a FAN failure indicated by a flashing SERVICE icon.  
Heat  
Cool  
On  
On  
Off  
On  
Service  
Each of these four signals have three  
different conditions. SeeTable I-P-3.  
Off  
On  
Flashing  
Service  
Flashing  
Note: There is no indication for a signal in the OFF condition. If Option 16 is set to 2,any flashing signals will  
also give audible buzzer indication  
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Installation  
Programming  
Figure I-P-9. BAYSENS019 complete icon display.  
Icon Descriptions  
9. Displays the desired state of either  
OCCUPIED or UNOCCUPIED.  
10. The padlock symbol indicates that the  
keyboard lockout is in effect.  
11. This extends the mode selection box  
in order to accommodate the  
emergency heat mode on the ZSM heat  
pump version.  
12. Fan mode selection box.  
13. Displayed in normal run mode when  
displaying the actual room  
temperature.  
14. Displayed in option setting mode only.  
15. Digits used to display temperature.  
16. HEAT and COOL have two functions:  
they indicate UCM status in normal run  
mode and indicate which type of  
setpoint is DESIRED during  
programming and override setting.  
17. Only used during programming and  
override setting to indicate the  
DESIRED setpoint temperature.  
18. Flashes when check filter timer is  
elapsed.  
19. Flashing cooling fail status indicator.  
20. Only used during UCP self-test mode.  
21. Flashing service status indicator and  
fan failure.  
22. Flashing heating fail status indicator.  
23. Operating MODE selection box.  
BAYSENS019 Icon Descriptions  
Refer to Figure I-P-9 for a pictorial view of  
the written descriptions below.  
1. The four periods of the day used only  
during programming mode.  
2. The seven days of the week used  
during programming and in normal  
mode to display the day (not current in  
Program Menu).  
3. Four digits used to display the time of  
day in normal run mode. Also used in  
Programming Menu andTemporary  
manual Override Menu, and options  
menu.  
4.Time of day colon used on the time of  
day clock. The colon blinks to indicate  
the UCM system is functional.  
5. AM and PM are used to indicate the  
time of day when using a 12 hour clock.  
AM and PM are not used when a 24  
hour clock is selected.  
6. DAYS and HOURS are used to set the  
override timer period.  
7. Displayed in temporary manual  
OVERRIDE mode, and when setting the  
override timer.  
8. Only used when setting the override  
timer.  
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Installation  
Programming  
Figure I-P-10. BAYSENS020 complete icon display.  
10. The padlock symbol indicates that the  
BAYSEN020 Icon Descriptions  
Refer to Figure I-P-10 for a pictorial view  
of the written descriptions below.  
1. The four periods of the day used only  
during programming mode.  
2. The seven days of the week used  
during programming and in normal run  
mode.  
3. Four digits used to display the time of  
day in normal run mode. Also used in  
Programming Mode, override timer  
setting menu, and options menu.  
4.Time of day colon used on the time of  
day clock. The colon blinks to indicate  
the UCM system is functional.  
5. AM and PM are used to indicate the  
time of day when using a 12 hour clock.  
AM and PM are not used when a 24  
hour clock is selected.  
6. DAYS and HOURS are used to set the  
override timer period.  
7. Displayed in temporary manual  
OVERRIDE mode, and when setting the  
override timer.  
8. Only used when setting the override  
timer.  
9. Displays the desired state of either  
OCCUPIED or UNOCCUPIED in the  
Programming, Run, and Menu.  
keyboard lockout is in effect.  
11. Operating mode selection box.  
12. Displayed in normal run mode when  
displaying the actual room  
temperature.  
13. Displayed in option setting mode only.  
14. Digits used to display temperature.  
15. HEAT and COOL have two functions:  
they indicate UCM status in normal run  
mode and indicate which type of  
setpoint is DESIRED during  
programming and override setting.  
16. Only used during programming and  
override setting to indicate the  
DESIRED setpoint temperature.  
17. Flashes when check filter timer is  
elapsed.  
18. Flashing cooling fail status indicator.  
19. Only used during UCP self-test mode.  
20. Flashing service status indicator and  
fan failure.  
21. Flashing heating fail status indicator.  
22. Used in programming mode to set  
HEAT SUPPLY AIR, COOL SUPPLY AIR,  
and MORNINGWARMUP  
temperatures.  
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Installation  
Programming  
Programming theTime Clock  
Option  
Programming  
Follow the instructions below for  
programming the time clock.  
To review and change programs:  
1.To review a program at any time, press  
Prog.key. Programs display in the  
sequence they were entered with  
repeated presses of Prog.key.  
2.To change a program, select that  
program as outlined in step 1. Enter the  
time of day and days of week just as in  
the programming steps above. The old  
program is overwritten with the new  
selections. Press Prog.to store the  
new program.  
Setting theTime  
1. Press Prog.key. 1234567 AM:—  
will appear in display. (Pressing Prog.”  
key again, display will show the number  
of free programs Fr 20). Press again  
to RETURN to 1st program.  
2. Press Bkey, ¤ON symbol will  
appear. Pressing the key again will  
toggle to OFF ¦. Select ON or OFF  
for the program.  
Important: Depress reset key before  
beginning to set time and program.  
1. Select military (24:00 hr.) or AM/PM  
(12:00 hr.) time mode by depressing  
and holding the hkey while pressing  
+ 1hkey to toggle between military  
and AM/PM. (AM appears in the display  
when in AM/PM mode.)  
2. Press and hold down ¹key.  
3. If setting the time when daylight  
savings time is in effect, press + 1h”  
key once (+ 1h will appear in display).  
4. Set hour with hkey. If AM or PM  
does not appear in display, the unit is in  
military time. See note above to  
change display.  
3. Press h+to select hour for switching  
time.  
4. Press m+to select minute for  
switching time.  
3.To delete an individual program, select  
the program as in step 1 and press h”  
and mkeys until “—:—” appears in  
the display. Press either Prog.or “¹”  
key until “—:—” flashes. The program  
is deleted after a few seconds.  
5. If the program is to occur every day of  
the week, (24 hour time control) ignore  
Daykey and press Prog.key to  
advance to program.  
6. For 7 day time control, press Day”  
key. 1 2 3 4 5 6 (Monday through  
Saturday) block of days appears in  
display. Pressing Daykey again, 1 2 3  
4 5 (Monday through Friday) appears in  
display. Repeated presses will cycle  
through all days of the week and back  
to 1 through 7 (Monday through  
Sunday). Select day or block of days  
desired.  
Manual Override  
While in the runmode (¹symbol is  
displayed), pressing the Bkey will  
reverse the load status (switch load off if  
it is on, or switch it on if it is off). A hand  
symbol appears in the display to indicate  
the override is active. At the next  
5. Set minutes with mkey.  
6. Press Daykey repeatedly to the day  
of the week. (1 is Monday, 7 is Sunday)  
7. Release ¹key, colon will begin  
flashing.  
scheduled switching time, automatic time  
control resumes, eliminating the override.  
Note: If keys h + or m + are kept de-  
pressed for longer than 2 seconds, a rapid  
advance of figures will result.  
Pressing the Bkey a second time  
[¤]appears in the display indicating  
the load is permanently on.  
The Digi 20electronic time switch is  
freely programmable for each day of the  
week in one minute increments. For easy  
and quick programming, the following 4  
block programs are available:  
Monday through Sunday  
7. Press Prog.key and repeat steps 2  
through 6a to enter additional  
programs of ON and OFF times. (Note  
that more than one OFF time may be  
programmed, enabling automatic  
control or manual overrides.)  
Pressing the Bkey a third time [¦]”  
appears in the display indicating the load  
is permanently off.  
Pressing the Bkey a fourth time  
returns to automatic, Bappears in the  
display.  
Monday through Saturday  
8. Press ¹key to enter run mode.  
Monday through Friday  
Saturday and Sunday  
All days shown in the respective blocks  
will switch on (or off) at the selected hour  
and minute.  
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Installation  
Startup  
Unit Startup Procedures  
1. Check all electrical connections for  
tightness.  
2. For water-cooled units: gain access to  
the liquid line service valves in the units  
left lower section.  
1. Ensure the fan rotation is in the  
direction of the arrow on the fan  
housing. If rotation is incorrect, first  
verify the incoming power phasing is  
correct. If it is correct, switch wires on  
the fan contact so the fan is properly  
phased.  
2. Check the fan belt condition and  
tension. Adjust the tension if belts are  
floppy or squeal continually. Replace  
worn or fraying belts in matched sets.  
3. Check voltage at all compressor  
terminals. Actual voltage should be  
within 10 percent of nameplate voltage.  
4. Check voltage imbalance from these  
three voltage readings, at each  
compressor. Maximum allowable  
voltage imbalance, phase to phase, is  
2%.  
wiring and make required changes to  
setpoint and sensor sources. See the  
IntelliPak ® Self-Contained Programming  
Guide, PKG-SVP01B-EN, for more  
information.  
Unit Startup  
Reference the IntelliPak ® Self-Contained  
Programming Guide, PKG-SVP01B-EN,  
for unit operating instructions. A copy  
ships with each unit.  
Note: Verify the liquid line service valve is  
open at unit start-up. Each compressor  
suction line contains a low pressure  
sensor that will shut the compressor down  
in low pressure situations. See Table O-SO-  
2 on page 97.  
For units with the VFD option, reference  
Instruction Bulletin, Altivar 58 Adjustable  
Drive Controllers and/or Installation  
Guide,Type H Controllers Keypad  
Display. A copy ships with eachVFD.  
ƽ CAUTION  
!
Never manually or automatically  
pump down below 7 psig. This  
will cause the compressor to  
operate in a vacuum and cause  
compressor damage.  
5. Check amp draw at compressor  
terminals. RLA and LRA is on the unit  
nameplate.  
6. Measure amp draw at evaporator fan  
motor terminals. FLA data is on the  
motor nameplate.  
7. After the system has stabilized (15 to  
30 minutes), check and record  
operating pressures and temperatures  
for all circuits.  
1. Be sure all system components are  
properly set and installed.  
2. Inspect all ductwork and duct  
connections.  
3. Remove compressor and fan  
assembly tie down bolts. However, on  
20-38 ton units, do not remove the fan  
assembly shipping blocks and tie down  
bolts if the fan speed is 750 rpm or less.  
When checking the operating pressures  
and conditions, establish nominal  
conditions for consistent measurements  
as follows:  
Leaving air greater than 60 F  
Entering air temperature between 70  
and 90 F  
Entering water temperature greater  
than 60 F  
Inlet guide vanes at least halfway open  
To start the unit, complete the following  
list in order:  
1. Apply power to the unit. Close the unit  
disconnect switch option.  
2. Make sure that the liquid line service  
valves are open on water cooled units.  
3. Adjust setpoints at the HI.  
See the IntelliPak® Self-Contained  
Programming Guide, PKG-SVP01B-EN,  
for available unit operating setpoints.  
Refer to the job specifications for proper  
setpoints.  
With all compressors running at full load:  
1. Compute superheat from the suction  
line pressure and temperature at the  
compressor on each circuit. Adjust the  
thermal expansion valve settings if  
necessary. Superheat should be  
between 12 and 17 F.  
2. Inspect refrigerant flow in the liquid line  
sight glass. Flow should be smooth and  
even, with no bubbles once the system  
has stabilized.  
Note: A sufficient cooling load must be  
visible to refrigerant circuit controls for the  
mechanical refrigeration to operate. If  
necessary, temporarily reduce the dis-  
charge air setpoint to verify the refrigera-  
tion cycle operation.  
Normal start-up can occur provided that  
Tracer Summit® is not controlling the  
module outputs or the generic BAS is not  
keeping the unit off.  
To ensure thatTracer Summit® has no  
affect on unit operation, removeTracer®  
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Installation  
Startup  
Startup Log  
Complete this log at unit start-up.  
Unit: ____________________________  
Unit Location: _________________________________________  
Unit Voltage: __________ __________ __________  
A
B
C
Evaporator:  
Evaporator fan motor horsepower: __________ Evaporator fan motor amps: __________ __________ __________  
A
B
C
Evaporator fan RPM (actual): ____________________  
Evaporator System Static (from test and balance report or actual readings):  
Supply Duct Static: __________  
Return Duct Static: __________  
Evaporator Air Conditions with both compressors operating:  
Enter:  
Dry Bulb - F: __________  
Leaving:  
Dry Bulb - F: __________  
Wet Bulb - F: __________  
Wet Bulb - F: __________  
Evaporator System CFM (test and balance sheet or actual tested): __________  
___________________________________________________________________________________________________________________________  
Compressor Amp Draw:  
Circuit A: __________ __________ __________ Circuit B: __________ __________ __________  
A
B
C
A
B
C
Circuit C: __________ __________ __________ Circuit D: __________ __________ __________  
A
B
C
A
B
C
Suction Pressure - psig:  
Circuit A: __________  
Circuit B: __________  
Circuit B: __________  
Circuit B: __________  
Circuit B: __________  
Circuit B: __________  
Circuit C: __________  
Circuit C: __________  
Circuit C: __________  
Circuit C: __________  
Circuit C: __________  
Circuit D: __________  
Circuit D: __________  
Circuit D: __________  
Circuit D: __________  
Circuit D: __________  
Discharge Pressure - psig: Circuit A: __________  
Super Heat - F: Circuit A: __________  
Liquid Line Pressure - psig: Circuit A: __________  
Sub Cooling - F: Circuit A: __________  
___________________________________________________________________________________________________________________________  
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Installation  
Startup  
Water Cooled Units:  
Circuit A:  
Entering WaterTemperature - F: __________ Leaving WaterTemperature - F: __________  
Entering Water Pressure - psig: __________ Leaving Water Pressure - psig: __________  
Circuit B:  
Enter WaterTemperature - F: __________  
Entering Water Pressure - psig: __________  
Circuit C:  
Leaving Water Temperature - F: __________  
Leaving Water Pressure - psig: __________  
Entering WaterTemperature - F: __________ Leaving WaterTemperature - F: __________  
Entering Water Pressure - psig: __________ Leaving Water Pressure - psig: __________  
Circuit D:  
Enter WaterTemperature - F: __________  
Leaving Water Temperature - F: __________  
Entering Water Pressure - psig: __________  
Leaving Water Pressure - psig: __________  
___________________________________________________________________________________________________________________________  
Air Cooled Units:  
(Data taken from outside condensing unit)  
Voltage: __________ __________ __________  
Amp Draw: __________ __________ __________  
A
B
C
A
B
C
Entering AirTemperature - F: __________  
Leaving AirTemperature - F: __________  
Refrigerant Pressures at condenser - psig: __________/ __________ Sub cooling at condenser - F: __________  
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Owner  
General  
Information  
Points List  
ECEM Module:  
Analog inputs  
Return air temperature  
Return air humidity  
RTM Module:  
Binary inputs  
Emergency stop  
External auto/stop  
Unoccupied/occupied  
Dirty filter  
In addition, units with a VOM have:  
Binary inputs  
VOM mode A, unit off  
VOM mode B, pressurize  
VOM mode C, exhaust  
VOM mode D, purge  
VOM mode E, purge w/duct pressure  
control  
VAV changeover with hydronic heat  
Binary outputs  
VAV box drive max (VAV units only)  
CV unoccupied mode indicator (CV units  
only)  
Alarm  
Fan run request  
Binary output  
V.O. relay  
Water pump request (water-cooled  
only)  
TCI Module:  
Analog input  
Binary input  
Enthalpy enable airside economizer  
Airside economizer damper minimum  
position  
Binary outputs  
Compressor on/off status  
Ventilation status  
Analog output  
Outside air damper actuator  
Condenser water flow status  
Heat status  
Heat Module:  
Analog output  
Analog outputs  
Supply air pressure  
Supply air temperature  
GBAS Module:  
Suction temperature of each circuit  
Entering economizer water temperature  
Zone temperature  
Binary inputs  
Demand limit contacts  
Entering condenser water temperature  
Supply air temperature reset signal  
Morning warmup sensor temperature  
Entering air temperature  
Binary outputs  
Dirty filter relay  
Refrigeration fail relay  
Heat fail relay  
Supply fan fail relay  
Active diagnostics  
Analog inputs  
Cooling and heating setpoints  
VAV discharge air temperature  
setpoints  
Analog inputs  
· Occupied zone cooling setpoint  
· Occupied zone heating setpoint  
·Unoccupied zone cooling setpoint  
· Unoccupied zone heating setpoint or  
minimum outside air flow setpoint  
· Supply air cooling setpoint  
Supply air pressure setpoint  
Cooling and heating enable/disable  
Air economizer enable/disable  
Airside economizer minimum position  
Unit priority shutdown  
· Supply air heating setpoint  
· Supply air static pressure setpoint  
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General  
Information  
Owner  
Unit Control Components  
as the source for economizer minimum  
position. If the RTM is the selected source  
for economizer minimum position, and if  
a valid resistance perTable O-GI-1 is  
provided to the RTM remote minimum  
position input, the OA cfm compensation  
function will not operate, even if enabled.  
Defaultis the only possible source for  
economizer minimum position when  
using the OA cfm compensation function.  
the unit wiring diagram when the unit  
returns to the occupied mode. This binary  
output signals theVAV boxes or other  
terminal devices to go full open.  
The Modular Series IntelliPak® self-  
contained unit is controlled by a  
microelectronic control system that  
consists of a network of modules. These  
modules are referred to as unit control  
modules (UCM). In this manual, the  
acronym UCM refers to the entire control  
system network.  
RTM Alarm Relay  
This is a single pole, double throw relay  
rated at a maximum voltage of 24 vac, 2  
amps max. Relay contacts can be  
programmed from the unit human  
interface. This relay can be programmed  
to pick up on any one or group of  
diagnostics from the HI.  
These modules perform specific unit  
functions using proportional/integral  
control algorithms. They are mounted in  
the unit control panel and are factory  
wired to their respective internal compo-  
nents. Each module receives and  
interprets information from other unit  
modules, sensors, remote panels, and  
customer binary contacts to satisfy the  
applicable request; i.e., economizing,  
mechanical cooling, heating, ventilation.  
Following is a detailed description of each  
modules function.  
Table GI-1. Economizer Remote Minimum  
Position Input Resistance.  
Status/Annunciator Output  
Input  
Economizer  
The status annunciator output is an  
internal function within the RTM module  
on CV andVAV units. It provides:  
a. diagnostic and mode status signals to  
the remote panel (LEDs) and to the HI.  
b. control of the binary alarm output on  
the RTM.  
Resistance  
Min. Position  
0 - 30 ohms  
0 %  
0-100 % (Linear)  
100 %  
30 - 240 ohms  
240 - 350 ohms  
> 350 ohms  
N/A *  
* Note: A resistance greater than 350 ohms is  
assumed to be an open circuit. The system will use  
the default minimum position value.  
RTM Analog Outputs  
c. control of the binary outputs on the  
GBAS module to inform the customer  
of the operational status and/or  
diagnostic conditions.  
The RTM has two 0-10 vdc outputs: one  
for the inlet guide vane option and one for  
the economizer option. These outputs  
provide a signal for one or two damper  
actuators. There are no terminal strip  
locations associated with these wires.  
They go directly from pins on the RTM  
circuit board to the actuator motor.  
RTM Module Board - Standard  
on all Units  
Occupied/Unoccupied Inputs  
There are four ways to switch to  
occupied/unoccupied:  
The RTM responds to cooling, heating,  
and ventilation requests by energizing the  
proper unit components based on  
information received from other unit  
modules, sensors, remote panels, and  
customer supplied binary inputs. It  
initiates supply fan, exhaust fan, exhaust  
damper, inlet guide vane positioning or  
variable frequency drive output, and  
airside economizer operation based on  
that information.  
1. Field-supplied contact closure  
hardwired binary input to the RTM  
2. Programmable night setback zone  
sensor  
RTM Binary Outputs  
The RTM has an output with pressure  
switch proving inputs for the supply fan.  
There is a 40 second delay from when  
the RTM starts the supply fan until the fan  
proving input must close. A fan failure  
diagnostic will occur after 40 seconds.  
This is a manual reset diagnostic, and all  
heating, cooling, and economizer  
functions will shut down. If this proving  
input is jumped, other nuisance  
3. Tracer Summit®  
4. Factory-mounted time clock  
VAV Changeover Contacts  
These contacts are connected to the RTM  
when daytime heating onVAV units with  
internal or external hydronic heat is  
required. Daytime (occupied) heating  
switches the system to operate as a CV  
unit. Refer to the unit wiring diagram for  
the field connection terminals in the unit  
control panel. The switch must be rated at  
12 ma @ 24 VDC minimum.  
Reference the RTM points list on page 77.  
Note: Emergency stop and external auto/  
stop, stop the unit immediately, emer-  
gency stop generates a manual reset  
diagnostic that must be reset at the unit  
human interface. External auto-stop will  
return the unit to the current operating  
mode when the input is closed, so this  
input is auto reset.  
diagnostics will occur. If the proving input  
fails to close in 40 seconds, the  
economizer cycles to the minimum  
position. This is a manual reset  
diagnostic. External control of the fan is  
not recommended.  
External Auto/Stop Switch  
A field-supplied switch may be used to  
shut down unit operation. This switch is a  
binary input wired to the RTM. When  
opened, the unit shuts down immediately  
and can be cancelled by closing the  
switch. Refer to the unit wiring diagrams  
(attached to the unit control panel) for  
proper connection terminals. The switch  
must be rated for 12 ma @ 24 VDC  
minimum. This input will override all VOM  
inputs, if the VOM option is on the unit.  
VAV Drive Max Output  
This is a single-pole, double-throw relay  
rated at a maximum voltage of 24 vac, 2  
amps. The relay contacts of this relay  
switch when the unit goes from the  
occupied mode to the unoccupied mode  
by means of the occupied binary input.  
The contacts will stay switched during the  
unoccupied and morning warmup mode.  
They will return to the position shown on  
RTM Remote Economizer Minimum  
Position  
The remote minimum position  
potentiometer, BAYSTAT023A, provides  
a variable resistance (0-270 ohms) to  
adjust the economizer minimum position  
from 0 to 100% when connected to the  
economizer remote minimum position  
input of the RTM. RTM must be selected  
78  
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Occupied/Unoccupied Contacts  
Table O-GI-2. RTM Sensor Resistance vs. Temperature  
To provide night setback control if a  
remote panel with night setback was not  
ordered, install a field-supplied contact.  
This binary input provides the buildings  
occupied/unoccupied status to the RTM. It  
can be initiated by a time clock, or a  
building automation system control  
output.The relays contacts must be rated  
for 12 ma @ 24 VDC minimum. Refer to  
the appropriate wiring diagrams  
Temperature (F)  
Resistance (ohms)  
346.1  
241.7  
170.1  
121.4  
103.0  
87.56  
74.65  
63.8  
Temperature (F)  
Resistance (ohms)  
11.60  
11.31  
11.03  
10.76  
10.50  
10.25  
10.00  
9.76  
-40  
-30  
-20  
-10  
-5  
71  
72  
73  
74  
75  
76  
77  
78  
79  
0
5
10  
15  
20  
25  
30  
35  
40  
45  
50  
55  
60  
65  
66  
67  
68  
69  
70  
54.66  
46.94  
40.40  
34.85  
30.18  
26.22  
22.85  
19.96  
17.47  
15.33  
13.49  
13.15  
12.82  
12.50  
12.19  
11.89  
6.53  
9.30  
8.25  
7.33  
5.82  
5.21  
4.66  
3.76  
3.05  
2.50  
2.05  
1.69  
1.40  
1.17  
0.985  
0.830  
80  
85  
90  
(attached to the unit control panel for the  
proper connection terminals in the unit  
control panel.  
100  
105  
110  
120  
130  
140  
150  
160  
170  
180  
190  
200  
Emergency Stop Input  
A binary input is provided on the RTM  
board for installation of a field-supplied  
normally closed (N.C.) switch to use  
during emergency situations to shut  
down all unit operations. When open, an  
immediate shutdown occurs. An  
emergency stop diagnostic enters the  
human interface and the unit will require  
a manual reset. Refer to the unit wiring  
diagrams (attached to the unit control  
panel for the proper connection  
terminals. The switch must be rated for  
12 ma @ 24 VDC minimum. This input  
will override all VOM inputs, if the VOM  
option is on the unit.  
Table O-GI-3. RTM Setpoint Analog Inputs  
Cooling or Heating Setpoint Input (F)  
Cooling Setpoint Input (F)  
VAV Box Option  
(using RTM as zone temp. source)  
(using RTM as supply air temp. source)  
Resistance (ohms)  
To interlockVAV box operation with  
evaporator fan and heat/cool modes,  
wire the VAV boxes/air valves to VAV box  
control connections on the terminal block.  
40  
45  
50  
55  
60  
65  
70  
75  
80  
NA  
NA  
40  
45  
50  
55  
60  
65  
70  
75  
80  
85  
90  
1084  
992  
899  
796  
695  
597  
500  
403  
305  
208  
111  
Supply Duct Static Pressure Control  
The RTM relies on input from the duct  
pressure transducer when a unit is  
equipped with IGV or VFD to position the  
IGV or set the supply fan speed to  
maintain the supply duct static pressure  
to within the static pressure setpoint  
deadband.  
RTM Sensors  
Table O-GI-4. RTM Resistance Value vs. System Operating Mode  
RTM sensors include: zone sensors with  
or without setpoint inputs and modes,  
supply air sensor, duct static pressure,  
outside air temperature, outside air  
humidity, airflow proving, and dirty filter.  
Resistance  
applied to RTM Mode  
input terminals (Ohms)  
CV Units  
VAV Units  
System Mode  
Off  
Fan Mode  
Auto  
Auto  
Auto  
On  
On  
On  
Auto  
On  
System Mode  
Off  
2320  
4870  
7680  
10,770  
13,320  
16,130  
19,480  
27,930  
Cool  
Auto  
Off  
Cool  
Auto  
Heat  
Heat  
Auto  
Note: Mode boundaries are 1000 to 40,000 ohms. Other boundaries are equal to the midpoint between the  
nominal mode resistance.  
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Compressor Module (SCM and Waterside Module - Standard  
activates, the one with the highest priority  
(VOM A) begins first, withVOM E”  
having lowest priority and beginning last.  
MCM - Standard on All Units  
onAllWater-Cooled Units  
The compressor module, (single circuit  
and multiple circuit) energizes the  
appropriate compressors and condenser  
fans upon receiving a request for  
mechanical cooling. It monitors the  
compressor operation through feedback  
information it receives from various  
protection devices.  
The waterside module (WSM) controls all  
water valves based on unit configuration.  
In addition, the WSM monitors waterflow  
proving and the following temperatures:  
entering water  
A description of theVOM binary inputs  
follows below.  
UNIT OFF sequence A”  
When complete system shut down is  
required, the following sequence can be  
used.  
Supply fan Off  
Supply fan VFD Off (0 Hz)  
(if equipped)  
Inlet guide vanes closed  
(if equipped)  
Outside air dampers Closed  
Heat all stages Off, Modulating heat  
output at 0 vdc  
Occupied/unoccupied output De-  
energized  
VO relay Energized  
entering air low  
mixed air  
entering condenser water  
refrigerant circuit 3:  
saturated condenser  
evaporator frost  
Human Interface Module -  
Standard on all units  
motor winding  
The human interface (HI) module enables  
the operator to adjust the operating  
parameters for the unit using it's 16-key  
keypad on the human interface panel.  
The HI panel provides a 2 line, 40  
character, clear language (English,  
Spanish, or French) LCD screen with unit  
status information and menus to set or  
modify operating parameters. It is  
mounted in the units main control panel  
and accessible through the units control  
panel door.  
refrigerant circuit 4:  
condenser  
evaporator  
motor winding  
Cooling Tower Interlock  
To interlock condenser pump/tower with  
cooling operation, wire the cooling tower  
to an external 115 volt control power  
source, to ground, and to control terminal  
block. Normally open/closed contacts are  
provided.  
Exhaust fan (field-installed) - Off  
Exhaust damper (field-installed) - Closed  
PRESSURIZE sequence B”  
This override sequence can be used if a  
positively pressured space is desired  
instead of a negatively pressurized space.  
Supply fan on  
Supply fan VFD on (60 Hz)  
(if equipped)  
Inlet guide vanes/VAV boxes open  
(if equipped)  
Outside air dampers open  
Heat all stages off, hydronic heat  
output at 0 vdc  
Heat Module  
Remote Human Interface  
Module Option  
The optional remote-mount human  
interface (RHI) panel has all the functions  
of the unit-mounted version except for  
service mode.To use a RHI, the unit must  
be equipped with an optional  
The heat module is standard on all units  
with factory-installed heat. It controls the  
unit heater to stage up and down to bring  
the temperature in the controlled space  
to within the applicable heating setpoint.  
Also, it includes a LEATPD, morning  
warmup, and heating outputs.  
Occupied/ unoccupied output - energized  
VO relay - energized  
Exhaust fan (field-installed) - off  
Exhaust damper (field-installed) - closed  
interprocessor communications bridge  
(IPCB). Model number digit 32 (=2)  
indicates if the ICPB was ordered with the  
unit. If not, contact your localTrane  
representative to order an ICPB kit for  
field installation. The RHI can be located  
up to 1,000 feet (304.8 m) from the unit. A  
single RHI can monitor and control up to  
four self-contained units if each one  
contains an IPCB. The IPCB switches must  
be set as SW1- off, SW2 - off, and SW3 -  
on.  
Ventilation Override Module  
(VOM) Option  
EXHAUST sequence C”  
The ventilation override module can be  
field-configured with up to five different  
override sequences for ventilation  
override control purpose. When any one  
of the modules five binary inputs are  
activated, it will initiate specified functions  
such as; space pressurization, exhaust,  
purge, purge with duct pressure control,  
and unit off.  
With the buildings exhaust fans running  
and the units supply fan off, the  
conditioned space becomes negatively  
pressurized. This is desirable for clearing  
the area of smoke when necessary; i.e.  
from an extinguished fire, to keep smoke  
out of areas that were not damaged.  
Supply fan off  
Interprocessor Communications Board •  
Option used with RHI  
Supply fan VFD off (0 Hz)  
(if equipped)  
Inlet guide vanes closed  
(if equipped)  
Outside air dampers closed  
Heat all stages Off, hydronic heat  
output at 0 vdc  
Occupied/unoccupied output de-  
energized  
Once the ventilation sequences are  
configured, they can be changed unless  
they are locked using the HI. Once locked,  
the ventilation sequences cannot be  
unlocked.  
The interprocessor communication board  
expands communications from the CSC  
unit's UCM network to a remote human  
interface panel. DIP switch settings on the  
IPCB module for this application are;  
switches 1 and 2 off,switch 3 on.”  
The compressors and condenser fans  
disable during the ventilation operation. If  
more than one ventilation sequence  
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Ventilation Control Module  
(VCM) -Available only with  
TraqDamper Option  
VO relay energized  
Exhaust fan (field-installed) - on  
Exhaust damper (field-installed) - open  
application are; switch 1 off,2 on,and  
3 off.”  
PURGE sequence D”  
Exhaust/Comparative  
Enthalpy Module (ECEM) - On  
Units with Comparative  
Enthalpy Option  
The exhaust/comparative enthalpy  
module receives information from the  
return air humidity sensor, and the RTM  
outside air temperature sensor and  
outside air humidity sensor, the outside  
air humidity sensor and temperature  
sensor to utilize the lowest possible  
enthalpy level when considering  
The ventilation control module (VCM) is  
located in the airside economizer section  
of the unit and linked to the units UCM  
network. Using a velocity pressure  
transducer/solenoid (pressure sensing  
ring) in the fresh air section allows the  
VCM to monitor and control fresh air  
entering the unit to a minimum airflow  
setpoint. See Figure O-GI-2 for a detail  
view of the velocity pressure transducer/  
solenoid assembly.  
This sequence could be used for purging  
the air out of a building before coming out  
of unoccupied mode of operation onVAV  
units. Also, it can be used to purge smoke  
or stale air.  
Supply fan on  
Supply fan VFD on (60 Hz)  
(if equipped)  
Inlet guide vanes/VAV boxes Open  
(if equipped)  
Outside air damper Open  
Heat all stages Off, Modulating heat  
output at 0 vdc  
Occupied/unoccupied output Energized  
VO relay Energized  
Exhaust fan (field-installed) - On  
Exhaust damper (field-installed) - Open  
An optional temperature sensor can be  
connected to the VCM to enable control  
of a field installed fresh air preheater.  
economizer operation. In addition, it  
receives space pressure information to  
maintain the space pressure within the  
setpoint control band. Refer to the Figure  
O-GI-1 for humidity vs. voltage values.  
Also, a field-provided CO2 sensor can be  
connected to the VCM to control CO  
reset. The reset function adjusts the2  
minimum cfm upward as the CO2  
concentrations increase. The maximum  
effective (reset) setpoint value for fresh  
air entering the unit is limited to the  
systems operating cfm.Table O-GI-5 lists  
the minimum outside air cfm vs. input  
voltage.  
PURGE with duct pressure control E”  
This sequence can be used when supply  
air control is required for smoke control.  
Supply fan on  
Supply fan VFD on (if equipped)  
Inlet guide vanes controlled by supply  
air pressure control function with  
supply air pressure high limit disabled  
Outside air dampers open  
Table O-GI-5. Minimum Outside Air  
Setpoint w/VCM Module and Traq™  
Sensing.  
Heat all stages off, hydronic heat  
output at 0 vdc  
Occupied/unoccupied output energized  
VO relay energized  
Exhaust fan (field-installed) - on  
Exhaust damper (field-installed) - open  
Unit  
InputVolts  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
0.5 - 4.5 vdc  
CFM  
SXWG 20  
SXWG 25  
SXWG 30  
SXWG 35  
SXRG 20  
SXRG 25  
SXRG 32  
6,350-8,500  
7,250-10,625  
7,250-12,750  
7,250-14,875  
7,250-8,500  
7,250-10,625  
7,250-13,600  
Figure O-GI-1. ECEM Relative Humidity vs.  
Voltage.  
Note: Each system (cooling, exhaust,  
supply air, etc.) within the unit can be  
redefined in the field for each of the five  
sequences, if required. Also the definitions  
of any or all of the five sequences may be  
locked into the software by simple key  
strokes at the human interface panel. Once  
locked into the software, the sequences  
cannot be changed.  
Trane Communications  
Interface Module (TCI) - Option  
used withTrane ICSTM  
TheTrane communication interface  
module allows external setpoints for  
most of the unit functions to be  
communicated to the unit's UCM network  
via aTrane ICSTM systems. DIP switch  
settings on the TCI module for this  
Figure O-GI-2. Velocity Pressure Trans-  
ducer/Solenoid Assembly.  
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Generic Building Automation  
System Module Option  
Any of the setpoint or output control  
parameters can be assigned to each of  
the four analog inputs on the GBAS  
module. Also, any combination of the  
setpoint and/or output control param-  
eters can be assigned to the analog  
inputs through the HI.To assign the  
setpoints apply an external 0-5 vdc  
signal:  
limiting is required, a command initiates  
to either partially (50%) or fully (100%)  
inhibit compressor and heater operation.  
This can be set at the HI using the setup  
menu, under the demand limit definition  
coolingand demand limit definition  
heatingscreens. A toggle switch, time  
clock, or building automation system  
control output can initiate demand  
limiting.  
The generic building automation system  
module (GBAS) provides broad control  
capabilities for building automation  
systems other than Tranes Tracer®  
system. A field provided potentiometer  
or a 0-5 vdc signal can be applied to any  
of the inputs of the GBAS to provide the  
following points:  
1. directly to the signal input terminals, or  
2. to the 5 vdc source at the GBAS  
module with a 3-wire potentiometer.  
If the cooling demand limit is set to 50%,  
half of the cooling capacity disables when  
the demand limit binary input closes. The  
heating demand limit definition can only  
be set at 100%, unless the unit has field-  
provided two-stage electric heat. In that  
case, if the heating demand limit is set to  
50%, half or one stage of heating disables  
when the demand limit binary input  
closes. If the demand limit definition is set  
to 100%, all cooling and/or heating will  
disable when the demand limit input  
closes.  
GBAS Analog Inputs  
Four analog inputs that can be configured  
to be any of the following:  
(1) Occupied zone cooling  
(2) Unoccupied zone cooling  
(3) Occupied zone heating  
(4) Unoccupied zone heating  
(5) SA cooling setpoint  
Note: There is a regulated 5 vdc output on  
the GBAS module that can be used with a  
potentiometer as a voltage divider. The  
recommended potentiometer value is  
1000-100,000 ohms.  
(6) SA heating setpoint  
(7) Space static pressure setpoint  
(8) SA static pressure setpoint  
The setpoints are linear between the  
values shown inTable O-GI-6 on page 83.  
ReferenceTable O-GI-7 on age 83 for  
corresponding input voltage setpoints.  
Following are formulas to calculate input  
voltage or setpoint. SP = setpoint, IPV =  
input voltage.  
GBAS Binary Outputs  
Five binary outputs to provide  
diagnostics, signaling up to five alarms.  
Each of the five (5) relay outputs can be  
mapped to any/all of the available  
diagnostics. Each output contains a dry  
N.O. and N.C. contact with aVA rating of 2  
amps at 24 VAC.  
GBAS Diagnostics (Binary Outputs)  
The GBAS can signal up to five alarm  
diagnostics, which are fully mappable  
using the setup menu on the HI. These  
diagnostics, along with the alarm output  
on the RTM, allow up to six fully  
If the setpoint range is between 50-90 F:  
IPV = (SP - 50) (0.1) + 0.5  
SP = [(IPV - 0.5)/0.1] + 50  
mappable alarm outputs.  
If the setpoint range is between 40-90 F:  
IPV = (SP - 40)(0.8) + 0.5  
SP = [(IPV - 0.5)/0.08] + 40  
GBAS Binary Input  
Each binary output has a NO and NC  
contact with a rating of 2 amps at 24VAC.  
The five binary outputs are factory preset  
as shown on the unit wiring diagram (on  
the unit control panel door). However,  
these outputs can be field defined in a  
variety of configurations, assigning single  
or multiple diagnostics to any output.  
One binary input for the self-contained  
unit to utilize the demand limit function.  
This function is operational on units with a  
GBAS and is used to reduce electrical  
consumption at peak load times. Demand  
limiting can be set at either 50% or  
100%. When demand limiting is needed,  
mechanical cooling and heating (with  
field-provided 2-stage electric heat only)  
operation are either partially (50%), or  
completely disabled (100%) to save  
energy.The demand limit definition is  
user definable at the HI panel. Demand  
limit binary input accepts a field supplied  
switch or contact closure. When the need  
for demand limiting discontinues, the  
units cooling/heating functions become  
fully enabled again.  
If the setpoint range is between 40-180  
F:  
IPV = (SP - 40)(0.029) + 0.5  
SP = [(IPV - 0.5)/0.029] + 40  
If the static pressure range is between  
0.03-0.3 iwc:  
IPV = (SP - 0.03)(14.8) + 0.5  
SP = [(IPV - 0.5)/14.8] + 0.03  
For a complete listing of possible diagnos-  
tics, see the IntelliPak® Self-Contained  
Programming Guide, PKG-SVP01B-EN.  
For terminal strip locations, refer to the  
unit wiring diagram for the GBAS.  
If the static pressure range is between  
0.0-5.0 iwc:  
IPV = (SP)(0.8) + 0.5  
SP = [IPV/(0.8 + 0.5)]  
GBAS Demand Limit Relay (Binary Input)  
The GBAS allows the unit to utilize the  
demand limit function by using a  
normally open (N.O.) switch to limit the  
electrical power usage during peak  
periods. Demand limit can initiate by a  
toggle switch closure, a time clock, or an  
ICScontrol output. These contacts must  
be rated for 12 ma @ 24 VDC minimum.  
GBAS Analog Inputs  
The GBAS accepts external setpoints in  
the form of analog inputs for cooling,  
heating, supply air pressure. Refer to the  
unit wiring diagram for GBAS input  
wiring and the various desired setpoints  
with the corresponding DC voltage input.  
When the GBAS module receives a  
binary input signal indicating demand  
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Table O-GI-6. GBAS Analog Input Setpoints  
Control Parameter  
Signal Range  
0.5 to 4.5 vdc  
Setpoint Range  
50 to 90 F  
Occupied Zone Cooling Setpoint  
(CV units only)  
Unoccupied Zone Cooling Setpoint  
(CV andVAV)  
Occupied Zone Heating Setpoint  
(CV units only)  
Unoccupied Zone Heating Setpoint  
(CV andVAV)  
Supply Air Cooling Setpoint  
(VAV units only)  
0.5 to 4.5 vdc  
0.5 to 4.5 vdc  
0.5 to 4.5 vdc  
0.5 to 4.5 vdc  
0.5 to 4.5 vdc  
50 to 90 F  
50 to 90 F  
50 to 90 F  
40 to 90 F  
40 to 180 F  
Supply Air Hydronic Heating Setpoint  
(VAV units only)  
Space Static Pressure Setpoint  
0.5 to 4.5 vdc  
0.5 to 4.5 vdc  
0.03 to 0.30 IWC  
0.0 to 5.0 IWC  
Supply Air Pressure Setpoint  
(VAV units only)  
Note: 1. Input voltages less than 0.5 vdc are considered as 0.5 vdc input signal is lost, the setpoint will  
clampto the low end of the setpoint scale. No diagnostic will result from this condition.  
2. Input voltages greater than 4.5 vdc are considered to be 4.5 vdc.  
3. The actual measured voltage is displayed at the HI.  
Table O-GI-7. GBAS Input Voltage Corresponding Setpoints  
Volts  
Temp.  
(F)  
Volts  
Temp.  
(F)  
Volts  
Temp  
(F)  
Volts  
Temp  
(F)  
0.5  
0.6  
0.7  
0.8  
0.9  
1.0  
1.1  
1.2  
1.3  
1.5  
50  
51  
52  
53  
54  
55  
56  
57  
58  
59  
1.6  
1.7  
1.8  
1.9  
2.0  
2.1  
2.2  
2.3  
2.4  
2.5  
60  
61  
62  
63  
64  
65  
66  
67  
68  
69  
2.6  
2.7  
2.8  
2.9  
3.0  
3.1  
3.2  
3.3  
3.4  
3.5  
70  
71  
72  
73  
74  
75  
76  
77  
78  
79  
2.7  
2.8  
2.9  
3.0  
3.1  
3.2  
3.3  
3.4  
3.5  
3.6  
80  
81  
82  
83  
84  
85  
86  
87  
88  
89  
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Waterside Components  
temperature is less than 58 F (15 C). This  
option allows the compressor to operate  
with entering fluid temperature down to  
35 F (2 C). The minimum valve position to  
maintain minimum condenser flow rates  
is user-defined at the HI. This valve drives  
closed if the unit shuts down or if a power  
failure occurs.  
units entering mixed air temperature by  
a minimum of 4 F plus the economizers  
approach temperature. The approach  
temperature default is 4 F. Waterside  
economizing disables when the units  
entering water temperature is not below  
the units entering mixed air temperature  
by at least the water economizer  
approach temperature. The approach  
temperature defaults to 4 F.The  
economizer acts as the first stage of  
cooling. If the economizer is unable to  
maintain the supply air setpoint, the unit  
control module brings on compressors as  
required to meet the setpoint.  
Waterside components consist of water  
piping, water valves, water flow switch  
option, water cooled condensers (SXWF  
only), and the economizer option.  
Water Purge  
This user-definable feature allows the  
user to select a purge schedule to  
automatically circulate water through the  
economizer and condensers periodically  
during non-operational times. This allows  
fresh chemicals to circulate in waterside  
heat exchangers. This feature is on all  
units and is defined at the HI.  
Water Flow Switch Option  
A water flow switch is factory installed in  
the condenser water pipe within the unit.  
Whenever the flow switch detects a  
water flow loss prior to or during  
mechanical cooling, compressor  
operation locks out and a diagnostic code  
displays. If water flow is restored, the  
compressor operation automatically  
restores.  
The waterside economizer includes a coil,  
modulating valves, controls, and piping  
with cleanouts. The coil construction is ½-  
inch (13 mm) OD seamless copper tubes  
expanded into aluminum fins. The  
evaporator and economizer coils share a  
common sloped (IAQ) drain pan. Drain  
pan options are either galvanized or  
stainless steel, and are insulated and  
internally trapped.  
Water Piping Options  
Water piping is factory-installed with left-  
hand connections. Units can be ordered  
with either basic piping or intermediate  
piping. Also, units with waterside  
ƽ WARNING  
!
To prevent injury or death due to  
instantaneous release of high  
pressure water, provide relief  
valves on system water piping.  
This will also help prevent water  
pump damage or stoppage due to  
excessive system pressure.  
economizers can be set for either  
variable or constant water flow at the HI.  
See Figures O-GI-3, O-GI-4, and O-GI-5 for  
detailed piping configuration information.  
With compatible piping configurations,  
the unit can be configured to provide:  
1) Constant water flow with basic or  
intermediate piping or 2) Variable water  
flow (head pressure control) with  
intermediate piping only.  
The waterside economizer coil is avail-  
able with either a two or four row coil,  
with no more than 12 fins per inch. The  
tubes are arranged in a staggered  
pattern to maximize heat transfer.The  
coil has round copper supply and return  
headers with removable cleanout and  
vent plugs. The optional mechanical  
cleanable economizer has removable  
cast iron headers to allow easy mechani-  
cal cleaning of the tubes. The waterside  
working pressure is rated for 400 psig  
(2758 kPa).  
Water-Cooled Condensers  
Constant water flow is for condenser  
pumping systems that are not capable of  
unloading the water-pumping system.  
Variable water flow maximizes energy  
saving by unloading the water pumping  
system.  
Units that are set up for variable water  
flow will modulate a water valve to  
maintain a user-defined condensing  
temperature setpoint. Condensing  
temperature will be referenced utilizing  
factory installed sensors located at each  
condenser.  
Basic Water Piping  
Waterside Economizer Flow Control  
Units equipped with a waterside  
economizer can be set from the human  
interface panel for variable or constant  
water flow.  
This option is available on units without a  
waterside economizer and with  
condenser water applications above 54 F  
(12.2 C) that do not require condensing  
pressure control. Left hand water  
connections and piping are extended to  
the unit exterior. Manifold piping is  
factory installed.  
Table O-GI-8. Water Condenser Connection  
Sizes  
Unit Size  
Direct  
Factory  
Piped  
2 1/2 NPT  
Condenser  
1 1/2 NPT  
Constant Water Flow  
SXWG 20-35  
Two-way modulating control shutoff  
valves are wired, controlled, and installed  
in the unit. One valve is located in the  
economizers water inlet, and the other is  
in the condenser bypass water inlet.  
When the waterside economizer enables,  
the two-way valves modulate to maintain  
the discharge air temperature setpoint.  
As the economizer valve opens, the  
Intermediate Water Piping  
This option provides condensing  
Waterside Economizer Option  
The waterside economizer option takes  
advantage of cooling tower water to  
either precool the entering air to aid the  
mechanical cooling process or, if the  
water temperature is low enough,  
temperature control when the unit is  
configured (user defined at the HI) for  
variable water flow with or without a  
waterside economizer. A two-way  
modulating control valve is wired and  
installed in the unit to maintains a specific  
range of water temperature rise through  
the condenser when entering fluid  
provide total system cooling. Waterside  
economizing enables when the units  
entering water temperature is below the  
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condenser bypass valve closes, and vice  
versa. Full water flow is always  
maintained through the condensers. Both  
valves will close in the event of a power  
failure. See Figures O-GI-3 and O-GI-5.  
Condenser 1  
Condenser 2  
Condenser 1  
Condenser 2  
V2  
Variable Water Flow  
Two-way modulating control shutoff  
valves are wired, controlled, and installed  
in the unit. One valve is located in the  
economizers water inlet, and the other is  
in the condenser bypass water inlet.  
When the economizer valve is active, the  
condenser bypass valve closes. The  
economizer valve modulates, thus water  
flow through the unit modulates. If the  
water is cool enough for economizing, but  
mechanical cooling is also required, the  
economizer valve fully opens to establish  
full water flow through the condensers.  
Whenever the water is too warm for  
economizing and there is a call for  
Figure O-GI-3. Basic water piping configu-  
ration, constant water flow.  
Figure O-GI-4. Intermediate water piping  
configuration, variable water flow.  
cooling, the economizer valve fully closes  
and the bypass valve fully opens,  
establishing full water flow through the  
condensers. Full water flow is always  
maintained through the condensers  
when mechanical cooling is required.  
Both valves close whenever cooling is  
not required, and in the event of a power  
failure. See Figures O-GI-4 and O-GI-5.  
Condenser 1  
Condenser 2  
Economizer  
V1  
V2  
Figure O-GI-5. Intermediate piping configuration with waterside  
economizer, variable or constant water flow.  
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Unit Airside Components  
the filters. When the differential pressure  
exceeds 0.9-inches (23 mm) WG, contact  
closure occurs and the HI will display a  
diagnostic. The unit will continue to run  
until you replace the air filters.  
position, the amount of spininduced by  
the vanes increases at the same time  
that intake airflow and fan horsepower  
diminish.The IGVs will close when the  
supply fan is off.  
The units air delivery system consists of  
condensers, dampers, enthalpy switch  
option, airside economizer option, filters,  
low ambient sensors, and factory  
mounted single or double wall plenums.  
A field installed indicator device may be  
wired to relay terminals to indicate when  
filter service is required. Contacts are  
rated at 115 VAC and are powered by a  
field supplied transformer.  
Supply Air Static Pressure Limit  
The opening of the IGVs andVAV boxes  
coordinate during unit startup and  
transition to/from occupied/unoccupied  
modes to prevent supply air duct  
overpressurization. However, if for any  
reason the supply air pressure exceeds  
the user-defined supply air static  
pressure limit set at the HI panel, the  
supply fan/VFD shuts down and the IGVs  
close. The unit will attempt to restart, up  
to three times. If the overpressurization  
condition still occurs on the third restart,  
the unit shuts down and a manual reset  
diagnostic sets and displays at the HI.  
SupplyAir Fan  
The unit has a single supply fan that runs  
at a constant speed. However, the fan  
may have the IGV or VFD option that  
modulates airflow based on supply air  
temperature control. Pressing the stop  
key on the HI will turn the supply fan off.  
The fan is on continuously when a CV unit  
is in occupied mode and except when a  
unit is in the night heat/morning warmup  
mode. During the night heat and setback  
mode the fan cycles on and off in  
Low Ambient Sensor (Air-Cooled Units)  
The low ambient sensor is field-installed  
on air-cooled units. Position it in a location  
subject to ambient temperatures only  
and not exposed to direct sunlight or  
exhaust fans.  
The low pressure cutout initiates based  
on the ambient temperature. A time  
delay on the low pressure cutout initiates  
for ambient temperatures between 50  
(zero minutes) and 0 F (10 minutes). This  
helps to prevent nuisance low pressure  
cutout trips.  
response to a call for heat. SeeTable O-  
GI-9 for available fan horsepower.  
Variable Frequency Drive Option  
The variable frequency drive (VFD) is  
driven by a modulating 0-10 vdc signal  
from the RTM module. A pressure  
transducer measures duct static  
pressure, and the VFD adjusts the fan  
speed to maintain the supply air static  
pressure within an adjustable user-  
defined range. The range is determined  
by the supply air pressure setpoint and  
supply air pressure deadband, which are  
set at the HI panel.  
Low Entering Air Temperature Sensor  
This is standard on all units with a  
hydronic coil or waterside economizer. It  
can also be ordered as an option.  
Inlet GuideVane Option  
A thermostat limit switch is factory  
mounted on the units entering air side  
with a capillary tube serpentine across  
the coil face. If the temperature falls  
below 35 F (2 C), the fan shuts down and  
the waterside economizer and/or  
hydronic heat valve options open to allow  
full water flow.The heat output also  
energizes. A manual reset is required.  
The low entering air temperature  
setpoint is adjustable.  
Inlet guide vanes (IGV) are driven by a  
modulating 0-10 vdc signal from the RTM  
module. A pressure transducer  
measures duct static pressure, and the  
IGV modulates to maintain the supply air  
static pressure within an adjustable user-  
defined range. The range is determined  
by the supply air pressure setpoint and  
supply air pressure deadband, which are  
set through the HI panel.  
VFDs provide supply fan motor speed  
modulation. The drives will accelerate or  
decelerate as required to maintain the  
supply air static pressure setpoint.  
IGV assemblies installed on the supply  
fan inlet regulate fan capacity and limit  
horsepower at lower system air require-  
ments. When in any position other than  
full open, the vanes pre-spin the air in the  
same direction as the supply fan rotation.  
As the vanes approach the full-closed  
High DuctTemperatureThermostat  
A factory-supplied temperature limit  
switch with reset element detects the  
supply air duct temperature. This sensor  
should be field-installed downstream  
from the units discharge in the supply air  
duct. If the supply air duct temperature  
exceeds 240 F (115.6 C), the unit shuts  
down and displays a diagnostic. A  
manual reset is required at the unit. The  
high duct temperature can be adjusted at  
the thermostat.  
VFD with Bypass  
Bypass control is an option that provides  
full nominal airflow in the event of drive  
failure. The user must initiate the bypass  
Table O-GI-9. Supply Fan Horsepower Selections.  
Unit Model  
HP  
5
7.5  
X
X
X
X
10  
X
X
X
X
15  
X
X
X
X
20  
X
X
25  
X
SXWG 20  
SXWG 25, 30, 35  
SXRG 20  
X
X
X
X
X
SXRG 25, 32  
X
Dirty Filter Sensor Option  
A factory installed pressure switch  
senses the pressure differential across  
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mode at the HI panel. When in bypass  
mode,VAV boxes need to be fully open.  
The self-contained unit will control  
heating and cooling functions to maintain  
setpoint from a user-defined zone sensor.  
Supply air static pressure limit is active in  
this mode.  
and permits the outdoor air damper to  
open only to the minimum position.  
can be enabled by the operator.  
The mixing box fabrication is 16-gauge  
galvanized steel. Opposed low leak  
damper blades are fabricated from 16-  
gauge galvanized steel and rotate on  
rustproof nylon bushings. A factory  
installed 24V modulating spring return  
actuator controls both damper positions.  
On water-cooled units, compressor  
operation lockout will not occur at low  
ambient air temperatures. However,  
lockout will still occur via low condenser  
water temperature.  
For more detailed information on VFD  
operation, reference the Square D VFD  
technical manual that ships with the unit.  
The outdoor air dampers drive fully  
closed whenever the supply air fan is off,  
provided there is power to the unit.  
Airside Economizers withTraqTM Damper  
Outside air enters the unit through the  
TraqTM damper assembly and is  
Airside Economizer Option  
Comparative Enthalpy Control  
Units with the airside economizer option  
are equipped with the necessary control  
sequences to use outside air for the first  
stage of cooling, in occupied or  
measured by velocity pressure flow  
rings. The velocity pressure flow rings  
are connected to a pressure transducer/  
solenoid assembly, which compensates  
for temperature swings that could affect  
the transducer.The ventilation control  
module (VCM) utilizes the velocity  
pressure input, the RTM outdoor air  
temperature input, and the minimum  
outside air CFM setpoint to modify the  
volume (CFM) of fresh air entering the  
unit as the measured airflow deviates  
from setpoint.  
Comparative enthalpy controls the  
economizer operation and measures  
temperature and humidity of both return  
air and outside air to determine which  
source has lower enthalpy.This allows  
true comparison of outdoor air and return  
air enthalpy by measurement of outdoor  
air and return air temperatures and  
humidities. A factory-installed control  
board, with field-installed outside and  
return air temperature and relative  
humidity sensors, allows monitoring of  
outside and return air.  
unoccupied mode and when ambient  
conditions are favorable for economizing.  
Inherent in the unit controller is the ability  
to suppress the setpoint below the  
normal unit setpoint. This allows the  
building to improve comfort levels when  
possible, and at the same time, optimize  
building mechanical cooling operation for  
peak operating efficiency. An outside air  
temperature and relative humidity  
sensor are provided to allow monitoring  
of reference enthalpy and are field  
installed.  
When the optional preheat temperature  
sensor is installed at the auxiliary  
Note: If comparative enthalpy is not  
ordered, the standard method compares  
outdoor air enthalpy with the fixed  
reference enthalpy. The reference  
enthalpy is set at the human interface  
panel.  
temperature on the VCM and the preheat  
function is enabled, the sensor will  
monitor the combined (averaged) fresh  
air and return air temperatures. As this  
mixed air temperature falls below the  
preheat actuate temperature setpoint,  
the VCM activates the preheat binary  
output to control a field-installed heater.  
The output deactivates when the tem-  
perature rises 5 F above the preheat  
actuate temperature setpoint.  
If the unit has the ECEM board, econo-  
mizer operation enables when the  
outside air enthalpy is less than 25 BTUs/  
lb. default (adjustable 19-28 BTUs/lb.).  
During occupied mode, the outside air  
damper opens to 15% (adjustable 0-  
100% at the HI) for ventilation purposes.  
Also, the ability to alter the outside air  
damper position to compensate forVAV  
supply air modulation is inherent in the  
unit controls, and can be enabled by the  
operator.  
Units with comparative enthalpy control  
are equipped with the necessary control  
sequences to allow using outside air for  
the first stage of cooling, in occupied or  
unoccupied mode and when ambient  
conditions are favorable for economizing.  
Inherent in the unit controller is the ability  
to suppress the setpoint below the  
normal unit setpoint. This allows the  
building to improve comfort levels when  
possible, and at the same time, optimize  
building mechanical cooling operation for  
peak operating efficiency.  
Using a field-installed CO2 sensor with  
CO2 reset enabled, as the CO concentra-  
tion increases above the CO22reset start  
value, the VCM modifies the minimum  
outside air CFM setpoint to increase the  
amount of fresh air entering the unit. The  
setpoint adjusts upward until reaching the  
CO2 maximum reset value. The maxi-  
mum effective (reset) setpoint value for  
fresh air is limited to the systems  
operating CFM. As the CO2 concentration  
decreases, the effective (reset) setpoint  
value adjusts downward toward the  
minimum outside air CFM setpoint. See  
Figure O-GI-6 on page 88 for an airflow  
cfm vs. CO2 concentration curve.  
If the unit does not have an ECEM board,  
it will economize when the O/A tempera-  
ture falls below the O/A economizer  
setpoint.  
The mixing box fabrication is 16-gauge  
galvanized steel. Opposed low leak  
damper blades are fabricated from 16-  
gauge galvanized steel and rotate on  
rustproof nylon bushings. A factory  
installed 24V modulating spring return  
actuator controls both damper positions.  
Economizer operation enables when the  
outside air enthalpy is 3 BTUs/lb. less  
than the return air enthalpy. During  
occupied mode, the outside air damper  
opens to 15% (adjustable 0-100%) for  
ventilation purposes. Also, the ability to  
alter the outside air damper position to  
compensate forVAV supply air modula-  
tion is inherent in the unit controls, and  
When outdoor conditions are not suitable  
for economizer cooling, the enthalpy  
control disables the economizer function  
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Standard Two-Position Damper Interface  
Units with the two-position damper  
interface are provided with a 0-10 VDC  
control output suitable for controlling a  
field-provided modulating actuator. In  
occupied mode, the output drives to the  
maximum position.  
control board, with outside and return air  
temperature and relative humidity  
sensors, are provided for monitoring  
outside and return air.The sensors are  
field installed. Economizer operation  
enables when the outside air enthalpy is  
3 BTUs/lb. less than the return air  
enthalpy. During occupied mode, the  
outside air damper opens to 15%  
(adjustable 0-100%) for ventilation  
purposes. Also, the ability to alter the  
outside air damper position to  
Air-Cooled Condensers  
SXRG units are designed for use with the  
remote air-cooled condenser, model  
CXRC. For more information, see the air-  
cooled condenser Installation, Owner, and  
Diagnostic Manual, CXRC-SVX01A-EN.  
SeeTable O-GI-10 for CXRC refrigerant  
connection sizes.  
Condenser fans will stage per a user-  
defined setting. If the condenser is  
equipped with head pressure control (air  
modulation on last stage of condenser  
capacity), the condenser airflow will  
modulate to maintain condensing  
temperature setpoint. Condensing  
temperature is determined by sensors  
located at each condenser coil.  
Airside Economizer Interface  
Units with airside economizer interface  
are equipped with the necessary control  
sequences to allow using outside air for  
the first stage of cooling, in occupied or  
unoccupied mode and when ambient  
conditions are favorable for economizing.  
Inherent in the unit controller is the ability  
to suppress the setpoint below the  
compensate forVAV supply air  
modulation is inherent in the unit  
controls, and can be enabled by the  
operator. An analog 2-10 VDC output  
(adjustable (0-10 VDC) is provided to  
modulate the field-provided 30-second  
damper actuators (adjustable 1-255  
seconds).  
normal unit setpoint. This allows the  
building to improve comfort levels when  
possible, and at the same time, optimize  
building mechanical cooling operation for  
peak operating efficiency. An outside air  
temperature and relative humidity  
sensor are provided for field installation  
to monitor reference enthalpy.  
Economizer operation enables when the  
outside air enthalpy is less than 25 BTUs/  
lb. (adjustable 19-28 BTUs/lb.). During  
occupied mode, the outside air damper  
opens to 15% (adjustable 0-100%) for  
ventilation purposes. Also, the ability to  
alter the outside air damper position to  
compensate forVAV supply air  
Figure O-GI-6. CO2 Reset Function, Outside Air vs. CO2.  
modulation is inherent in the unit controls,  
and can be enabled by the operator. An  
analog 2-10 VDC output (adjustable (0-10  
VDC) is provided to modulate the field-  
provided 30 second damper actuators  
(adjustable 1-255 seconds).  
Table O-GI-10. Remote Air-Cooled Condenser Refrigerant Connection Sizes - English  
inches (Metric, mm)  
Unit  
Size  
Circuit 1  
Circuit 1  
Circuit 2  
Circuit 2  
Airside Economizer Interface with  
Comparative Enthalpy  
Liquid Line  
Discharge Line  
Liquid Line  
Discharge Line  
5
5
CXRC 20, 25, 29, 30  
/
1 1/8  
/
1 1/8  
8
8
Units with airside economizer interface  
and comparative enthalpy are equipped  
with the necessary control sequences to  
allow using outside air for the first stage  
of cooling, in occupied or unoccupied  
mode and when ambient conditions are  
favorable for economizing. Inherent in the  
unit controller is the ability to suppress  
the setpoint below the normal unit  
setpoint. This allows the building to  
improve comfort levels when possible,  
and at the same time, optimize building  
mechanical cooling operation for peak  
operating efficiency. A factory-installed  
(16)  
(29)  
(16)  
(29)  
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Input Devices and System  
Functions  
Following are basic input device and  
system function descriptions used within  
the UCM network on IntelliPak® self-  
contained units. Refer to the unit wiring  
diagrams for specific connections.  
all compressor operation for that circuit,  
and initiates a manual reset diagnostic.  
SCM/MCM for circuits 1 and 2 (air or  
water cooled), and WSM for circuits 3  
and 4 (only water-cooled).  
Low Pressure Control  
Low pressure (LP) control uses a binary  
input device. LP cutouts are mounted on  
the suction lines near the compressors.  
Head Pressure Control  
Head pressure control is accomplished  
using two saturated refrigerant  
temperature sensors on air-cooled units  
and up to four sensors on water-cooled  
units.  
The LP control contacts close when the  
suction pressure exceeds 27 4 psig. If  
the LP control is open when a compres-  
sor starts, none of the compressors on  
that circuit will operate. They are locked  
out and a manual reset diagnostic  
initiates.  
Water Purge  
During the unoccupied mode, water-  
cooled units will periodically circulate  
water through the condensers and  
waterside economizer if the user has  
enabled the purge function at the HI.  
Air-cooled units: During a request for  
compressor operation when the con-  
densing temperature rises above the  
lower limit of the control band, the  
compressor module (SCM/MCM)  
sequences condenser fans on. If the  
operating fans cannot bring the condens-  
ing temperature to within the control  
band, more fans turn on. As the satu-  
rated condensing temperature ap-  
proaches the lower limit of the control  
band, fans sequence off. The minimum  
on/off time for condenser fan staging is  
5.2 seconds. If the system is operating at  
a given fan stage below 100% for 30  
minutes he saturated condensing  
temperature is above the efficiency  
check point setting, a fan stage will be  
added. If the saturated condensing  
temperature falls below the efficiency  
check point setting, fan control remains at  
the present operating stage. If the fan  
stage cycles four times within a 10  
minute period, the lower limit tempera-  
ture is redefined as being equal to the  
lower limit minus the temporary low limit  
suppression setting. The unit will utilize  
this new low limit temperature for one  
hour to reduce condenser fan short  
cycling.  
The water purge function circulates  
water to introduce fresh water-treatment  
chemicals and help prevent water  
stagnation. The number of hours be-  
tween each periodic purge, or purge  
duration, is user-defined at the HI  
between 1-999 hours. If the periodic  
purge timer expires while the unit is in  
occupied mode, it will wait for the next  
available unoccupied time before  
initiating water purge. Contrary, if a  
request for cooling occurs during a purge  
sequence, purge will terminate and  
cooling will commence.  
The LP cutouts open if the suction  
pressure approaches 7 4 psig. If the LP  
cutout opens after a compressor starts,  
all compressors operating on that circuit  
will turn off immediately and will remain  
off for a minimum of three minutes.  
If the LP cutout trips four consecutive  
times during the first three minutes of  
operation, the compressors on that circuit  
will lock out and a manual reset diagnos-  
tic initiates.  
Evaporator Temperature Sensor  
Frostat™  
The evaporator temperature sensor is an  
analog input device that monitors  
refrigerant temperature inside the  
evaporator coil to prevent coil freezing. It  
is attached to the suction line near the  
evaporator coil with circuits 1 and 2  
connected to the SCM/MCM and circuits  
3 and 4 connected to the WSM. The coil  
frost cutout temperature is factory set at  
30 F. It is adjustable at the HI from 25-35 F.  
The compressors stage off as necessary  
to prevent icing. After the last  
compressor stages off, the compressors  
restart when the evaporator  
temperature rises 10 F above the coil  
frost cutout temperature and the  
minimum three minute offtime  
elapses.  
Compressor Circuit Breakers  
The compressors are protected by circuit  
breakers that interrupt the compressor  
power supply if the current exceeds the  
breakers must tripvalue. During a  
request for compressor operation, if the  
compressor module (MCM or SCM)  
detects a problem outside of its normal  
parameters, it turns any operating  
compressor(s) on that circuit off, locks out  
all compressor operation for that circuit,  
and initiates a manual reset diagnostic.  
Water-cooled: Units without WSE, the  
condenser valve modulates to maintain  
an average saturated condenser  
Compressor Motor Winding Thermostats  
A thermostat is embedded in the motor  
windings of each compressor. Each  
thermostat opens if the motor windings  
exceed approximately 221 F. The  
thermostat resets automatically when  
the winding temperature decreases to  
approximately 181 F. Rapid cycling, loss  
of charge, abnormally high suction  
temperature. Units with WSE, if econo-  
mizing and mechanical cooling is neces-  
sary the economize valve will sacrifice  
free cooling and modulate to maintain  
condensing saturated temperature. If not  
economizing, the condenser valve will  
modulate to maintain condensing  
saturated temperature.  
Saturated Condenser Temperature  
Sensors  
The saturated condenser temperature  
sensors are analog input devices used on  
all units. They are mounted inside a  
temperature well located on a condenser  
tube bend on air-cooled units, and in the  
condenser shell on water-cooled units.  
The sensors monitor the saturated  
refrigerant temperature inside the  
condenser coil and are connected to the  
temperatures, or the compressor running  
backwards could cause the thermostat to  
open. During a request for compressor  
operation, if the compressor module  
detects a problem outside of it's normal  
parameters, it turns any operating  
Water-cooled units without head pres-  
sure control will lock out mechanical  
cooling at entering condenser water  
temperatures below 54 F. Mechanical  
cooling will resume when the entering  
compressor(s) on that circuit off, locks out  
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General  
Information  
Owner  
condenser water temperature exceeds  
58 F.  
Units with VFD w/bypass have fuses to  
protect VFD circuit and overloads to  
protect the motor when in bypass.  
water temperature falls to 34 F, open the  
economizer valve, and energize the  
pump output.  
Low Ambient Control (Air-Cooled Units  
Only)  
Supply Air Temperature Low Limit  
The supply air temperature low limit  
function uses the supply air temperature  
sensor input to modulate the economizer  
damper to the minimum position if the  
supply air temperature falls below the  
occupied heating setpoint temperature.  
High DuctTempThermostat Option On  
Units with a TCI  
The low ambient modulating output on  
the compressor module is functional on  
all units with or without the low ambient  
option. When the compressor module  
stages up to it's highest stage (stage 2 or  
3 depending on unit size), the modulating  
output is 100% (10 VDC). When the  
control is at stage 1, the modulating  
output (0 to 10 VDC) controls the  
The high duct temperature thermostats  
are binary input devices used on units  
with aTrane communication interface  
module (TCI). The high duct temperature  
thermostat provides a high limit unit  
shutdown and requires a manual reset.  
The thermostats are factory set to open if  
the supply air temperature reaches 240 F,  
or the return air temperature reaches  
135 F. Once tripped, the thermostat  
requires a manual reset. Reset by  
pressing the sensors reset button when  
the air temperature decreases  
Supply Air Temperature Sensor  
The supply air temperature sensor is an  
analog input device. It monitors the  
supply air temperature for supply air  
temperature control, supply air  
temperature reset, supply air  
temperature low limiting, and supply air  
tempering. It is mounted in the supply air  
discharge section of the unit and  
connected to the RTM.  
saturated condensing temperature to  
within the programmable condensing  
temperature low ambient control point.  
Low Ambient Compressor Lockout (Air-  
Cooled Units Only)  
approximately 25 F below the cutout  
point.  
The low ambient compressor lockout  
utilizes an analog input device. When the  
system is configured for low ambient  
compressor lockout, the compressors will  
not operate if the temperature of the  
outside air falls below the lockout  
setpoint. When the temperature rises 5 F  
above the lockout setpoint, the  
compressors will operate. The setpoint  
for units without the low ambient option is  
50 F. For units with the low ambient  
option, the setpoint is 0 F. The setpoints  
are adjustable at the human interface  
panel.  
Filter Switch  
Supply Airflow Proving Switches  
The filter switch is a binary input device  
used on units to measure the pressure  
differential across the unit filters. It is  
mounted in the filter section and  
connected to the RTM. A diagnostic  
SERVICE signal displays at the remote  
panel if the pressure differential across  
the filters is at least 0.5w.c.The contacts  
automatically open when the pressure  
differential across the filters decrease to  
0.4w.c.The switch differential is field  
adjustable between 0.17to 5.0w.c.  
0.05 .  
This is binary input device used on units  
to signal the RTM when the supply fan is  
operating. It is mounted in the supply fan  
section and is connected to the RTM.  
During a request for fan operation and if  
the differential switch opens for 40  
consecutive seconds, compressor  
operation turns off, heat operation turns  
off, the request for supply fan operation is  
turns off and locks out, IGV option closes,  
economizer damper option closes, and a  
manual reset diagnostic initiates.  
Return Air Temperature Sensor  
The return air temperature sensor is an  
analog input device used with a return  
humidity sensor on units with the  
Low Entering Air Protection Device  
The low entering air protection device  
(LEATPD) is a binary input on units with  
hydronic heat or a waterside economizer.  
It is optional on all water-cooled units.  
High Duct Static Switch Option  
The high duct static switch is field-  
mounted in the ductwork or plenums with  
smoke dampers. It will cause a manual  
reset diagnostic if the duct static exceeds  
the preset static limit. The static limit is  
adjustable at the HI.  
comparative enthalpy option. The sensor  
monitors the return air temperature and  
compares it to the outdoor temperature  
to establish which temperature is best  
suited to maintain cooling requirements.  
It is mounted in the return air path and  
connected to the ECEM.  
If the LEATPD is on a unit with factory-  
installed heat, it is mounted in the heat  
section and connected to the heat  
module. If the entering air temperature to  
the heating coil falls to 40 F, the normally  
open contacts on the LEATPD close and  
cause the following events:  
a. the hydronic heat actuator fully opens.  
b. the supply fan turns off  
c. the outside air damper closes  
d. the SERVICE light at the remote zone  
sensor option turns on.  
Supply Fan Circuit Breaker, Fuses, and  
Overloads  
The supply fan motor is protected by  
either circuit breakers fuses or a  
combination of fuses and overloads,  
dependent upon unit configuration. Circuit  
breakers are used on units without VFDs.  
They will trip and interrupt the motor  
power supply if the current exceeds the  
breaker trip value. The RTM shuts all  
system functions off when detecting an  
open fan proving switch. Units with VFDs  
have fuses to protect theVFD and motor.  
e. a LEATPD diagnostic displays at the  
human interface panel.  
If the LEATPD is on a water-cooled unit  
without factory-installed heat, it is wired  
to the WSM. It will trip if the entering  
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Sequence of  
Operation  
Owner  
Control Sequences of  
Operation  
on the unoccupied input for more than  
five seconds.  
temperature is below the MWU setpoint,  
the unit enters the MWU mode.  
For units with supply air temperature  
control entering the unoccupied mode,  
the following sequence will occur:  
Heating/cooling functions cease and the  
economizer option closes fully.The  
supply fan shuts down for proper cool-  
down time of the heat exchanger.  
However, the supply fan may remain  
on for a short period of time.  
After the supply fan shuts down, the  
occupied/unoccupied relay energizes  
and the IGV option fully opens. Also, the  
VAV box stroke time begins.TheVAV  
box stroke time is field adjustable to  
allow time forVAV boxes to go to the  
full open airflow position.  
Morning Warmup  
Occupied/Unoccupied Switching  
There are four ways to switch occupied/  
unoccupied:  
This feature can be enabled at the HI, and  
can be used with factory or field-installed  
heat. If MWU is not required disable the  
function in the setup menu at the HI.  
MWU transitions the zone from  
(1) Night setback zone sensor  
(2) Field-supplied contact closure  
(hardwired binary input to RTM)  
(3) Tracer Summit®  
unoccupied to occupied. It will heat until  
the MWU setpoint is met. The unit is then  
released to occupied mode. Supply duct  
static pressure is maintained during this  
sequence. MWU can be set (at the HI) to  
function as either full or cycling capacity.  
(4) Factory-mounted time clock  
Field Supplied Occupied/Unoccupied  
Input on the RTM  
This input accepts a field supplied switch  
or contacts closure, such as a time clock,  
with a rating of 12 mA at 24 VDC  
minimum.  
Full Capacity Morning Warmup (MWU)  
Full capacity morning warmup uses full  
heating capacity to heat the zone as  
quickly as possible. Full heating capacity  
is provided until the morning warmup  
setpoint is met. At this point, the unit is  
released to daytime mode.  
Tracer Summit® System  
TheTracer Summit® system can control  
the occupied/unoccupied status of the  
self-contained unit.  
After the maxVAV box stroke time  
expires and the IGVs are fully open, the  
supply fan, economizer (if enabled),  
compressors, and heat enable to satisfy  
the unoccupied zone temperature  
setpoints.  
Factory MountedTime Clock  
A time clock can control the  
occupied/unoccupied status of the  
self-contained unit.  
Cycling Capacity Morning Warmup  
(MWU)  
Cycling capacity morning warmup  
provides a more gradual heating to  
overcome building sinkas the zone is  
heated. Normal zone temperature control  
with varying capacity is used to raise the  
zone temperature to the MWU zone  
temperature setpoint. This method of  
warmup is used to overcome the  
building sinkeffect.  
Note: Unoccupied economizer operation  
can be enabled or disabled at the HI or  
using Tracer Summit®.  
Unoccupied  
The unoccupied mode helps conserve  
energy during times when a building is  
usually unoccupied. When in unoccupied  
mode, the unit will control to the  
unoccupied setpoints (usually a lower  
heating setpoint and higher cooling  
setpoint). Setpoints can be programmed  
at the HI,Tracer Summit®, or the night  
setback zone sensor.  
For units without volume control entering  
the unoccupied mode, the following  
sequence will occur:  
The occupied/unoccupied relay  
energizes and the economizer option  
fully closes.  
The fan mode is set to auto and the unit  
will control to the unoccupied zone  
temperature setpoints.  
Reference Figure O-SO-1 for a pictorial  
explanation of the cycling MWU se-  
quence. Cycling capacity MWU will heat  
until MWU temperature setpoint is  
reached. Next a 60 minute timer begins. If  
the building load reaches the MWU  
ventilation setpoint, or the 60 minutes  
expire, whichever is first, the airside  
economizer will control to the minimum  
position. MWU will end when the zone  
temperature rises above the MWU  
terminate setpoint.  
The unit enters the unoccupied mode  
when the RTM receives a closed signal  
With MWU enabled at the HI, if the zone  
Figure O-SO-1. Typical cycling morning warmup cycle.  
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Sequence of  
Operation  
Owner  
Timed Override Activation - ICS™  
This function is operational whenever the  
units RTM module is used as the zone  
temperature sensor source, which can be  
set at the HI panel. When this function is  
initiated by the push of the override  
button on the zone sensor, the unit will  
switch to the occupied mode. Unit  
operation (occupied mode) during timed  
override is terminated by a signal from  
Tracer®.  
VAV Drive Max Output  
This is a single-pole, double-throw relay  
rated at a maximum voltage of 24 vac, 2  
amps max. The relay contacts of this  
relay switch when the unit goes from the  
occupied mode to the unoccupied mode  
by means of the unoccupied binary input,  
night setback zone sensor, orTracer  
Summit®. The contacts will stay switched  
during the unoccupied and morning  
warmup mode. They will return to the  
position shown on the unit wiring  
Timed Override Activation - Non-ICS  
This function is active whenever the units  
RTM module board is selected as the  
zone temperature source, which can be  
set at the human interface panel. When  
this function is initiated by the push of the  
override button on the zone sensor, the  
unit will switch to the occupied mode.  
Automatic cancellation of the timed  
override mode occurs after three hours  
of operation.  
diagram when the unit returns to the  
occupied mode. The intent of this binary  
output is to signal theVAV boxes or other  
terminal devices to go to a full open  
airflow position.  
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Sequence of  
Operation  
Owner  
Occupied Sequence Of  
Operation  
by modulating the economizer option  
and/or staging mechanical cooling on and  
off as required. The changeover relay  
contacts (field supplied) must be open on  
units with hydronic heat for cooling to  
operate.  
perature setpoint, which is user-defined  
at the HI. Minimum on/off timing of  
compressors prevents rapid cycling.  
All setpoints can be adjusted using the HI  
panel. Also, cooling/heating setpoints can  
be adjusted in the zone, if using one of the  
zone sensor options (BAYSENS020,  
BAYSENS021, BAYSENS008,  
When both airside and waterside  
economizers are on a single unit, priority  
must be set at the HI. The economizer  
with the highest priority attempts cooling  
first. Once it is operating at its maximum,  
and if additional cooling is necessary, the  
other economizer enables before  
Cooling  
BAYSENS010, BAYSENS019, or  
Upon entering occupied mode, the RTM  
receives an input from either the HI, RHI,  
Tracer Summit®, or the GBAS to start the  
supply fan. The RTM supply fan contacts  
close and energize the supply fan  
BAYSENS014). For a complete list of unit  
setpoint default values and ranges, see  
the IntelliPak® Self-Contained  
mechanical cooling begins.  
Programming Guide, PKG-SVP01B-EN.  
Cooling/Waterside Economizer  
Waterside economizing enables when  
the units entering water temperature is  
below the units entering mixed air  
temperature by 4 F plus the user  
adjustable economizer approach  
temperature. The approach temperature  
default is 4 F.  
contactor. On units with IGV, the fan  
delays until the IGV fully close. When the  
supply fan starts, the fan proving switch  
closes, signaling the RTM that airflow is  
established. Depending on unit options,  
either the IGV will begin to drive open or  
the VFD will ramp the fan, and/or the  
airside economizer dampers will open to  
the user-defined minimum position.  
Occupied ZoneTemperature - Cooling  
The unit transitions from unoccupied to  
occupied when the occupied/unoccupied  
input on the RTM is open for more than  
five seconds after having been closed.  
This input can be received fromTracer  
Summit®, the remote NSB zone sensor,  
the timed override function, or a field  
supplied contact. Dependent on unit  
options and the HI programming, the  
following sequence will occur:  
The unit will begin MWU and then  
switch to the occupied mode after the  
MWU setpoint is met.  
Purge will be enabled byTracer  
Summit®.ThenTracer Summit® will  
enable the occupied mode.  
Waterside economizing disables when  
the units entering water temperature is  
not below the units entering mixed air  
temperature by at least the water  
economizer approach temperature  
(default value of 4 F). The economizer  
acts as the first stage of cooling. If the  
economizer is unable to maintain the  
zone or supply air temperature setpoint,  
the compressor module will bring on  
compressors as required to meet the  
setpoint.  
When a cooling request is sent to the  
RTM from the zone sensor, the RTM  
evaluates the system operating condi-  
tions using the supply air and outdoor  
temperature input before sending the  
request to the MCM for mechanical  
cooling. If outdoor conditions (tempera-  
ture and humidity) are suitable or the  
EWT is within specified setpoints, the  
RTM will attempt to use free cooling”  
without using any compressors. The RTM  
will use either the airside or waterside  
economizer option. When outdoor air  
conditions are not suitable, only mechani-  
cal cooling will function and outside air  
dampers will remain at their minimum  
position. If the unit does not have an  
economizer, mechanical cooling will  
operate to satisfy cooling requirements.  
The unit will switch from unoccupied to  
occupied control immediately.  
Upon entering occupied mode, the IGV  
option will close while the supply fan  
remains on. The occupied/unoccupied  
relay will de-energize.  
Cooling/Airside Economizer  
On units with an airside economizer, a call  
for cooling will modulate the fresh air  
dampers open. The rate of economizer  
modulation is based on deviation of the  
zone temperature from setpoint; i.e., the  
further away from setpoint, the faster the  
fresh air damper will open. The first stage  
of cooling will start after the economizer  
reaches full open.  
Zone Temperature Control  
Unit Model Number Digit 9 = 4 or 5  
A zone sensor located directly in the  
space sends input to the RTM while the  
CV unit is in occupied cooling mode.  
When the unit is in occupied cooling, the  
RTM controls the zone temperature  
within the cooling setpoint deadband by  
modulating the economizer option and/or  
staging mechanical cooling on and off as  
required.  
Units With Economizer  
If the entering condenser water  
temperature (units with a WSE) or the  
outside air enthalpy (units with an ASE) is  
appropriate to use free cooling,the  
economizer will attempt to satisfy the  
cooling zone temperature setpoint.  
Note: The airside economizer will only  
function freely if ambient conditions are  
below the enthalpy control settings or  
below the return air enthalpy if unit has  
comparative enthalpy installed. If outside  
air is not suitable for “economizing,” the  
fresh air dampers drive to the minimum  
open position. A field adjustable, factory  
default setting at the HI panel or Tracer  
Summit® can provide the input to establish  
the minimum damper position.  
Note: When using an ASE with econo-  
mizer enabled, O/A temperature enable  
can be used instead of comparative  
enthalpy if the O/A temperature falls below  
the economizer setpoint.  
Supply Air Temperature Control  
Unit Model Number Digit 9 = 1, 2, 3, or 6  
When the unit is in occupied cooling, the  
RTM controls the supply air temperature  
to the specified supply air cooling setpoint  
Then compressors will stage on as  
necessary to maintain supply air tem-  
When outdoor air conditions are above  
the setpoint or comparative enthalpy  
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Sequence of  
Operation  
Owner  
control setting, only mechanical cooling  
will function and outside air dampers will  
remain at their minimum position.  
deadband are user defined at the HI  
panel.  
Supply Air Tempering (Hot Water and  
Steam VAV Units Only)  
When supply air temperature falls below  
the supply air temperature deadband low  
end, the heating valve modulates open to  
maintain the minimum supply air  
temperature setpoint.  
Hydronic Heat: Hot Water or Steam  
On units with hot water or steam heating,  
the zone temperature can be controlled  
to a heating setpoint during the occupied  
mode. The zone temperature heating  
setpoint and deadband are user defined  
at the HI panel or zone sensor.VAV  
occupied heating initiates by closing a  
field-supplied switch or relay contacts  
connected to the changeover input on the  
RTM. Supply air static pressure is  
maintained.  
Mechanical Cooling  
If the zone temperature cannot be  
maintained within the setpoint deadband  
using the economizer option or if there is  
no economizer, the RTM sends a cooling  
request to the MCM. The compressor  
module checks the compressor  
protection circuit before closing stage  
one. After the first functional stage starts,  
the compressor module monitors the  
saturated refrigerant temperature and  
closes the condenser fan output contact  
when the saturated refrigerant  
Daytime Warmup (Units with Supply Air  
Temperature Control Only)  
During occupied mode, if the zone  
temperature falls to a preset, user-  
defined zone low limit temperature  
setpoint, the unit is put into daytime  
warmup. The system changes over to CV  
heating, theVAV boxes drive full open.  
However, unit airflow modulation control  
operates to maintain duct static setpoint,  
and full heating capacity is provided until  
the daytime warmup setpoint is reached.  
The unit is then returned to normal  
occupied mode.  
Supply Air Setpoint Reset (VAV Units  
Only)  
temperature rises above the lower limit  
setpoint.  
Supply air reset can be used to adjust the  
supply air temperature setpoint on the  
basis of a zone temperature or outdoor  
air temperature. Supply air reset  
adjustment is available at the HI panel for  
supply air heating and supply air cooling  
control.  
Air-Cooled Units Only  
The compressor module closes the  
condenser fan output contact when the  
saturated refrigerant temperature rises  
above the lower limit setpoint.  
Supply AirTempering  
Supply air tempering is available on units  
without volume control and with hot  
water, steam, or electric heat or units with  
supply air temperature control with  
steam or hot water heat. When the unit is  
in heat mode but not actively heating, if  
the supply air temperature drops to 10 F  
(5.5 C) below the occupied zone heating  
temperature setpoint, electric heat will  
stage on or the hydronic valve will  
modulate to maintain a minimum supply  
air temperature. The unit transitions out  
of heat mode if the supply air  
Water-Cooled Units Only  
Reset based on outdoor air temperature  
Outdoor air cooling reset is sometimes  
used in applications where the outdoor  
temperature has a large effect on  
building load. When the outside air  
temperature is low and the building  
cooling load is low, the supply air setpoint  
can be raised, thereby preventing  
The WSM modulates the condenser coil  
water valves to maintain condenser  
temperature, if applicable. Otherwise, it  
will check the entering condenser water  
temperature to ensure it is greater than  
54 F or if not, it will lock out cooling.  
Auto Changeover (Units with Heat )  
When the system mode is in auto, the  
mode will change to cooling or heating as  
necessary to satisfy the zone cooling and  
heating setpoints. The zone cooling and  
heating setpoints can be as close as 2 F  
(1.1 C).  
subcooling of critical zones. This reset can  
lower usage of mechanical cooling, thus  
savings in compressor kW, but an  
increase in supply fan kW may occur.  
temperature rises to 10 F (5.5 C) above  
the occupied zone heating temperature  
setpoint.  
Outdoor air heating reset is the inverse of  
cooling, with the same principles applied.  
Occupied ZoneTemperature - Heating  
Relies on input from a sensor directly in  
the space, while a system is in occupied  
heating mode or an unoccupied period, to  
stage electric heat on and off or modulate  
the hydronic heating valve as required to  
maintain the zone temperature within the  
heating setpoint deadband. The supply  
fan will operate when there is a request  
for heat.  
For both outdoor air cooling reset and  
heating reset, there are three user  
defined parameters that are adjustable  
through the human interface panel.  
Beginning reset temperature  
Changeover  
This mode only functions on units with  
supply air temperature control and  
hydronic heat. When the changeover  
binary input is closed the unit will control  
to a discharge air heating setpoint. This  
setpoint is entered at he HI, and can be a  
higher temperature than the supply air  
cooling setpoint. This function maintains  
duct static pressure.  
Ending reset temperature  
Maximum amount of temperature reset  
Reset based on zone temperature  
Zone reset is applied to the zone(s) in a  
building that tends to overcool or  
overheat. The supply air temperature  
setpoint is adjusted based on the  
temperature of the critical zone(s). This  
can have the effect of improving comfort  
and/or lowering energy usage. The user-  
defined parameters are the same as for  
outdoor air reset.  
Electric Heat  
On units with electric heat, the zone  
temperature can be controlled to a  
heating setpoint during the occupied  
mode by cycling a single stage electric  
heater. An interface is provided for field  
supplied single stage electric heat. The  
zone temperature heating setpoint and  
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Sequence of  
Operation  
Owner  
Compressors  
Compressor Cycling  
Compressor Lead/Lag Operation  
Compressor lead/lag is a user-selectable  
feature at the HI panel and is available on  
all units. After each request for  
compressor operation, the lead  
refrigeration circuit or compressor  
switches, thereby causing a more  
equitable or balanced run time among  
compressors.  
Compressors cycle to maintain the  
operating state required by the  
temperature controls. In the event of a  
compressor failure, the next available  
compressor turns on. Refer toTable O-  
SO-1 for compressor cycling by unit  
model and tons.  
Units use two sizes of hermetic scroll  
compressors, 10 and 15 hp, and can use  
from two to four compressors. When  
viewing the front of the unit, compressors  
are identified A through B from left to  
right.The second compressor from the  
left, or B compressor, is always the first to  
come on, unless locked out for a  
malfunction or shut off on frost protection.  
Refer toTable O-SO-1 for compressor  
cycling stages andTable O-SO-3 on page  
96 for percent cooling capacity by stage.  
During normal conditions, compressors  
will not shut off until they have been on  
for at least three minutes and will not turn  
on until they have been off for at least  
three minutes. Normal operating condi-  
tions are established on an individual  
compressor basis. When a compressor  
starts, its timer also starts. The compres-  
sor evaporator circuit frost protection can  
override the minimumtimer and  
reduce the five minute minimum re-  
quired time period.  
When lead/lag is enabled, each time the  
system cycles, it will alternate between  
the standard compressor staging and the  
lead/lag staging. UsingTable O-SO-1, a  
SXWG 30-ton unit will first stage com-  
pressor B then A, then AB for first cycle  
and A, then AB for the second cycle.  
Appropriate condenser valves (water-  
cooled and condenser fans (air-cooled)  
will stage with appropriate compressors  
to maintain saturated condensing  
The control system logic permits com-  
pressor operation only after the supply  
fan is on. If the supply fan shuts down,  
compressors will not operate. Units  
without head pressure control (units with  
intermediate piping packages) will lock  
out mechanical cooling when the entering  
condenser water temperature falls below  
54 F. Mechanical cooling will resume  
when the entering condenser water  
temperature exceeds 58 F.  
temperature. Enabling lead/lag may drop  
a cooling stage when compared to  
standard staging. SeeTable O-SO-1 for  
compressor staging.  
When the unit is powered up, or manually  
reset there will be a three to eight minute  
delay before the first compressor may be  
turned on as requested by the unit  
temperature control algorithm.  
Table O-SO-1. Compressor Stages.  
Unit  
Size  
Refrigerant  
Circuit Type  
Model # Digit 5  
Compressor HP  
by Stage  
Standard  
Compressor  
Staging  
Lead/Lag  
Compressor  
Staging  
SCM  
or  
MC  
A
B
SXWG 20, 25  
SXRG 20  
SXWG 30  
SXRG 25  
SXWG 35  
SXRG 32  
Independent  
Independent  
Independent  
10 10  
15 10  
15 15  
B/AB  
A/AB  
A/AB  
A/AB  
MCM  
MCM  
MCM  
B/A/AB  
B/AB  
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Operation  
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Compressor Safety Devices  
The compressors have motor  
control band region.  
The supply air temperature control band  
is centered around supply air tempera-  
ture setpoint and is adjustable from 2 to  
12 F. In a steady state, the unit will either  
maintain a constant level of cooling  
capacity with the supply air temperature  
within the control band, or the highest  
active cooling level will cycle to provide  
an average supply air temperature equal  
to the setpoint.  
temperature cutout switches in the motor  
windings. These switches are provided to  
take the compressors off line during high  
motor winding temperature conditions.  
If a compressor low pressure cutout  
opens during compressor start-up, the  
UCM will not shut the compressor off  
during the first two to three minutes after  
start-up. This prevents possible nuisance  
trips during low ambient start conditions.  
See Table O-SO-2.  
If the supply air temperature swings  
outside the limits of the control band, the  
mechanical cooling capacity will increase  
or decrease by one level accordingly.The  
change occurs by integrating the tem-  
perature offset from the control band  
limit.  
Each compressors discharge line  
contains a high pressure cutout. Under  
abnormal operating conditions, the cutout  
will open to stop compressor operation.  
Table O-SO-2. Pressure Cutouts.  
A minimum time delay of five minutes  
follows each change in cooling level. This  
time delay promotes stability by allowing  
the system to respond to the change  
before any further control action occurs.  
As the supply air temperature ap-  
proaches setpoint, the time duration  
between changing levels of cooling  
capacity increases.  
Unit  
High Pressure  
Cutout  
Low Pressure  
Cutout  
Model  
SXWG  
SXRG  
360/270  
425/350  
20/35  
12/27  
Step Control  
Steps of mechanical cooling are control  
based on supply air or zone temperature.  
SeeTable O-SO-1 on page 95 for  
compressor staging.  
See Figure O-SO-2 for the typical unit  
operating curve. Figure O-SO-3 shows  
typical unit performance when supply air  
temperature swings exceed the control  
band limits.  
Capacity is based on an integrating  
control concept. The unit capacity  
matches the existing load and maintains  
an average supply air temperature within  
the supply air setpoint temperature  
Adjust the supply air temperature control  
Table O-SO-3. IntelliPak®Unit Cooling Capacity Percent.  
Cooling Stage % Utilized  
UnitTons  
SCWG 20  
SCWG 25  
SCWG 30  
SCWG 35  
Cool 1  
53  
Cool 2  
100  
Cool 3  
n/a  
53  
100  
n/a  
47  
53  
65  
100  
100  
n/a  
Table O-SO-4. Thermostat Controlled Unit Cooling Capacity  
Stages.  
Unit  
Size  
Cooling Stages  
Cool 1  
Cool 2  
% Capacity Utilized % Capacity Utilized  
SCWG 20  
SCWG 24  
SCWG 30  
SCWG 35  
53  
53  
65  
53  
100  
100  
100  
100  
SCRG 20  
SCRG 25  
SCRG 32  
52  
47  
52  
100  
100  
100  
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Sequence of  
Operation  
Owner  
band according to the desired unit  
performance. Increasing the control band  
reduces the equipment cycle rate and  
increases the maximum potential supply  
air temperature deviation from setpoint.  
Conversely, decreasing the control band  
reduces the maximum potential tem-  
perature deviation, but increases the  
compressor cycle rate.  
Follow these recommendations concern-  
ing the supply air temperature control  
band settings based on expected unit  
sizing:  
2 Cooling stage unit: 9 F  
3 Cooling stage unit: 7 F  
4 Cooling stage unit: 6 F  
Figure O-SO-2. Typical pulldown curve for unit operating properly within control band.  
Low Ambient Compressor Lockout  
This function will lock out the compressor  
if the outdoor air temperature sensor  
reads an outdoor temperature below the  
low ambient compressor lockout  
temperature setpoint. This setpoint is  
adjustable at the human interface panel.  
Compressors will lock out when outdoor  
air temperature falls below that selected  
temperature and will start again when  
the temperature rises 5 F above the  
setpoint.  
Evaporator Coil Frost Protection  
FROSTAT™  
The FROSTATsystem eliminates the  
need for hot gas bypass. It utilizes an  
evaporator temperature sensor mounted  
on the suction line near the TXV bulb of  
each circuit to protect the evaporator  
from freezing.  
Figure O-SO-3. Typical pulldown curve for unit operating improperly outside control band.  
If the evaporator temperature ap-  
proaches the specified setpoint (adjust-  
able between 25 and 35 F at the HI) the  
compressor(s) will cycle off. The supply  
fan remains on to help de-ice the coil. The  
compressors will restart when the  
evaporator temperature has risen 10 F  
above the specified cutout temperature  
and when the compressor(s) have been  
off a minimum of three minutes. This  
prevents rapid cycling of the compres-  
sors.  
Service Valves  
Service valves are factory installed on  
each circuit before and after the  
compressor to allow compressor  
isolation for servicing.  
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Maintenance  
Maintenance Procedures  
efficiency particulate arrestance (HEPA)  
filters with a minimum efficiency of  
99.97% at 0.3 micron particle size.  
5. Thoroughly clean the contaminated  
area(s) with a mild bleach and water  
solution or an EPA-approved sanitizer  
specifically designed for HVAC use.  
Carefully follow the sanitizer  
manufacturers instructions regarding  
product use.  
6. Immediately rinse the drain pan  
thoroughly with fresh water to prevent  
potential corrosion from the cleaning  
solution.  
7. Allow the unit to dry thoroughly before  
putting the system back into service.  
8. Determine and correct the cause of  
any microbial contamination.  
9. Be careful that the contaminated  
material does not contact other areas of  
the unit or building. Properly dispose of  
all contaminated materials and cleaning  
solution.  
surfaces following the procedure below:  
Air Filters  
1. Disconnect all electrical power to the  
unit.  
2. Don the appropriate personal  
protective equipment (PPE).  
3. Use a portable vacuum with HEPA  
filtration to remove the loose dirt and  
organic matter.The filter should be  
99.97% efficient at 0.3 micron particle  
size.  
4. If no microbial growth (mold) exists,  
thoroughly clean the fan and associated  
components with an industrial cleaning  
solution. Carefully follow the cleaning  
solution manufacturers instructions  
regarding personal protection and  
ventilation when using their product.  
5. If microbial growth is present, remove  
the contamination (Step 2) and  
thoroughly clean the affected area with  
an EPA-approved sanitizer specifically  
designed for HVAC use. Carefully follow  
the sanitizer manufacturers instructions  
regarding the product usage.  
6. Rinse the affected surfaces thoroughly  
with fresh water and a fresh sponge to  
prevent potential corrosion of metal  
surfaces.  
7. Allow the unit to dry completely before  
putting it back into service.  
Filter access doors are on the same side  
of the unit as the water piping  
connections.To replace throwaway  
filters, remove the dirty elements and  
install new filters with the filters  
directional arrows pointing toward the  
fan. Verify that no air bypasses the filters.  
All unit sizes require four 16 x 25 x 2 inch  
(508 x 635 x 51 mm) and four 20 x 25 x 2  
inch (508 x 635 x 51 mm) filters.  
Inspecting and Cleaning the  
Drain Pan  
Check the condensate drain pan and  
drain line to ensure that the condensate  
drains properly at least every six months  
or as dictated by operating experience.  
If evidence of standing water or  
condensate overflow exists, take steps to  
identify and remedy the cause  
Note: Standing water in drain pans can  
promote microbial growth (mold) which  
may cause unpleasant odors and serious  
health-related indoor air quality problems. If  
microbial growth is found, it must be  
removed immediately and that portion of  
the unit properly cleaned and sanitized.  
immediately. Refer to the trouble  
shooting section of this manual for  
possible causes and solutions. If microbial  
growth is evident in the drain pan,  
remove and clean it immediately. Clean  
drain pans using the following procedure:  
8. Ensure that contaminated material  
does not contact other areas of the unit  
or building. Properly dispose of all  
contaminated materials and cleaning  
solution.  
1. Disconnect all electrical power to the  
unit.  
2. Don the appropriate personal  
protective equipment (PPE).  
3. Remove all standing water.  
4. Use a scraper or other tools to remove  
and solid matter. Remove solid matter  
with a vacuum device that utilizes high  
Inspecting and Cleaning the  
Fan  
Inspect the fan section every six months  
or more frequently if operating  
experience dictates. Clean accumulated  
dirt and organic matter on the fan interior  
Determine the cause of any microbial  
growth (mold) and take action to ensure it  
does not reoccur.  
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Maintenance  
Supply Fan  
each sheave and pull it tight for a center  
line. See Figure O-M-2 on page 100 for  
recommended torques.  
4. Once the sheaves are properly aligned,  
tighten sheave set screws to proper  
torque.  
Fan Drive  
Perform the following procedures  
according to the Periodic Maintenance  
Check Liston page 110.  
5. Check belt tension. Refer to the  
Measuring BeltTensionsection on  
page 100.  
6. If required, adjust belt to the minimum  
recommended tension. Refer to  
Adjusting BeltTensionsection on  
page 100.  
7. Retighten bearing set screws to the  
proper torques after aligning the  
sheaves.  
8. Check the fan bearing locking collars  
for tightness on the shaft.To tighten the  
locking collar, loosen the set screw and  
slide the collar into its proper position  
over the extended end of the inner  
case.Tighten the set screw to the  
appropriate torque value.  
WARNING  
!
Disconnect electrical power  
source to prevent injury or death  
from electrical shock.  
1. Rotate the fan wheel to be sure it turns  
freely in the proper direction and is not  
rubbing on the fan housing, inlet, or inlet  
guide vanes. If necessary, center the  
fan wheel again.  
2. Check the position of both shafts. Fan  
and motor shafts should operate  
parallel to each other for maximum belt  
and bearing life. Shim as necessary  
under the motor or fan bearings to  
obtain proper alignment.  
9. During air balancing, verify the sheave  
alignment, belt tension, and that the  
shaft is parallel.  
3. Check the fan motor sheave alignment  
with straight edge or a tightly pulled  
string. For sheaves of different widths,  
place a string in the center groove of  
Figure O-M-1. Fan shaft and motor sheave alignment.  
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Maintenance  
Fan Bearings  
Adjusting BeltTension  
Recommended belt tension range values  
are on the unit fan scroll.To access the  
fan scroll, face the right-hand side of the  
unit and remove the top left panel. The  
belt tension label is on the top right-hand  
corner of the fan scroll. See Figures O-M-  
4.  
The opposite drive end bearing is a  
special bearing with close tolerance fit of  
balls and races. Replace this bearing with  
the same part number as the original  
bearing.  
To adjust belt tension refer to Figure O-M-  
2 and perform the following procedure:  
1. Loosen bolts A, B, and E on both sides  
of the sliding motor base. See Figure O-  
M-4.  
2. Loosen nuts C and D (as required for  
motor horsepower) to slide the motor  
on its mounting plate in the proper  
direction to tension or relieve tension on  
the belt.  
3. Adjust nuts A-D and bolt E. Do not  
stretch the belts over the sheaves.  
4. Retighten all nuts and bolts.  
5.Verify tension is adjusted properly.  
Fan BeltTension  
The correct operation tension for aV-belt  
drive is the lowest tension at which the  
belt will not slip under the peak load  
conditions. It may be necessary to  
increase the tension of some drives to  
reduce flopping or excessive start-up  
squealing.  
Note: Check fan belt tension at least twice  
during the first days of new belt operation  
since there is a rapid decrease in tension  
until belts are run-in.  
Proper belt tension is necessary to  
endure maximum bearing and drive  
component life and is based on fan brake  
horsepower requirements. If frayed or  
worn, replace belts in matched sets.  
CAUTION  
!
Do not over-tension the belts.  
Excessive tension will reduce fan  
and motor bearing life, accelerate  
belt wear, and possibly cause  
shaft failure.  
Measuring BeltTension  
Measure fan belt tension with a  
Browning, Gates, or equivalent belt  
tension gauge. Determine deflection by  
dividing the belt span distance (in inches)  
by 64. See Figure O-M-2.  
Recommended belt tension range values  
are on the unit fan scroll. The belt tension  
label is on the top right-hand corner of the  
fan scroll. See Figure O-M-4.  
Follow the procedure below to measure  
belt tension.  
1. Measure belt span between centers of  
sheaves and set the large Oring of  
the tension gauge at 1/64 inch for each  
inch of belt span.  
Deflection = Belt Span/64  
Figure O-M-3. Belt Tension Gauge.  
2. Set the load Oring at zero.  
3. Place the large end of the gauge at the  
center of the belt span. Press down until  
the large Oring is even with the top  
of the belt line or the next belt as in  
Figure O-M-2. Place a straight edge  
across the sheaves as a reference  
point. See Figure O-M-1 on page 99.  
4. Remove the gauge. Note that the load  
Oring now indicates a number on the  
plunger scale. This number represents  
pounds of force required to deflect the  
belt.  
5. Check the reading from step 4 against  
the values given on the unit fan scroll. If  
necessary, readjust belt tension.  
Figure O-M-4. Location of fan belt label on  
fan scroll.  
Figure O-M-2. Fan Belt Adjustment.  
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Maintenance  
Figure O-M-5. Fan assembly.  
Figure O-M-6 . Fan motor adjustment points.  
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Maintenance  
Refrigerant System  
Follow specific manufacturers  
guidelines for conversion of existing  
systems.  
To assist in reducing power generation  
emissions, always attempt to improve  
equipment performance with improved  
maintenance and operations that will  
help conserve energy resources.  
Special Note on Refrigerant Emissions  
Follow theTrane recommended  
procedures on operation, maintenance,  
and service to ensure refrigerant  
conservation and emission reduction.  
Also, pay specific attention to the  
following:  
Whenever removing refrigerant from  
air conditioning or refrigerating  
equipment, recover for reuse, recycle,  
reprocess (reclaim), or properly  
destroy it.  
Always determine possible refrigerant  
recycling or reclaiming requirements  
before beginning recovery. Questions  
about recovered refrigerants and  
acceptable refrigerant quality  
standards are addressed in ARI  
Standard 700.  
ƽ WARNING  
!
WARNING: Do not work in a  
closed area where refrigerant or  
nitrogen gases may be leaking. A  
sufficient quantity of vapors may  
be present and cause injury.  
ƽ WARNING  
!
Use approved containment vessels  
and safety standards. Comply with all  
applicable transportation standards  
when shipping refrigerant containers.  
To minimize emissions while  
recovering refrigerant, use recycling  
equipment. Always attempt to use  
methods which will pull the lowest  
possible system vacuum while  
recovering and condensing refrigerant  
into containment.  
WARNING: Do not use oxygen,  
acetylene, or air in place of  
refrigerant and dry nitrogen for  
leak testing. A violent explosion  
may result causing injury or  
death.  
ƽ WARNING  
!
When leak checking with trace  
refrigerant and nitrogen, use HCFC22  
(R22) rather than CFC12 (R12) or any  
other fully halogenated refrigerants.  
Be aware of any new leak test  
methods which eliminate refrigerant  
as a trace gas.  
When cleaning system components or  
parts, do not use CFC11 (R11) or  
CFC113 (R113). Refrigeration system  
clean up methods using filters and  
dryers are recommended. Do not use  
solvents which have ozone depletion  
factors. Properly dispose of used  
materials.  
WARNING: Always use a pressure  
regulator, valves, and gauges to  
control drum and line pressures  
when pressure testing the  
system. Excessive pressures may  
cause line ruptures, equipment  
damage, or an explosion which  
may result in injury or death.  
ƽ WARNING  
!
WARNING: Do not exceed 200  
psig when leak testing the  
system. Damage to the unit could  
result, or an explosion may occur  
causing injury or death  
Take extra care to properly maintain all  
service equipment directly supporting  
refrigerant service work such as  
gauges, hoses, vacuum pumps, and  
recycling equipment.  
Stay aware of unit enhancements,  
conversion refrigerants, compatible  
parts, and manufacturers  
recommendations that will reduce  
refrigerant emissions and increase  
equipment operating efficiencies.  
In the event of required system repair,  
leak test the liquid line, evaporator coil,  
and suction line at pressures dictated by  
local codes, and using the following  
guidelines.  
1. Charge enough refrigerant and dry  
102  
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Maintenance  
refrigerant service work such as  
gauges, hoses, vacuum pumps, and  
recycling equipment.  
Stay aware of unit enhancements,  
conversion refrigerants, compatible  
parts, and manufacturers  
recommendations that will reduce  
refrigerant emissions and increase  
equipment operating efficiencies.  
Follow specific manufacturers  
guidelines for conversion of existing  
systems.  
To assist in reducing power generation  
emissions, always attempt to improve  
equipment performance with improved  
maintenance and operations that will  
help conserve energy resources.  
nitrogen into the system to raise the  
pressure to 100 psig.  
ƽ CAUTION  
!
2. Use a halogen leak detector, halide  
torch, or soap bubbles to check for  
leaks. Check interconnecting piping  
joints, the evaporator coil connections,  
and all accessory connections.  
3. If a leak is detected, release the test  
pressure, break the connections and  
reassemble it as a new joint, using  
proper brazing techniques.  
4. If no leak is detected, use nitrogen to  
increase the test pressure to 150 psig  
and repeat the leak test. Also, use soap  
bubbles to check for leaks when  
nitrogen is added.  
5. Retest the system to make sure new  
connections are solid.  
6. If a leak is suspected after the system  
has been fully charged with refrigerant,  
use a halogen leak detector, halide  
torch, or soap bubbles to check for  
leaks.  
Caution: Do not operate the  
compressors without some  
refrigerant in each circuit. Failure  
to do so may damage the  
compressors.  
Charge refrigerant into the system by  
Refrigerant System  
Special Note on Refrigerant Emissions  
Follow theTrane recommended  
procedures on operation, maintenance,  
and service to endure refrigerant  
conservation and emission reduction.  
Also, pay specific attention to the  
following:  
When removing refrigerant from air  
conditioning or refrigerating equipment  
recover for reuse, recycling,  
reprocessing (reclaim), or properly  
destroy it.  
Always determine possible refrigerant  
recycling or reclaiming requirements  
before beginning recovery. Questions  
about recovered refrigerants and  
acceptable refrigerant quality  
Refrigerant Leak Testing  
ƽ WARNING  
!
Do not work in a closed area  
where refrigerant or nitrogen  
gases may be leaking. A  
sufficient quantity of vapors may  
be present and cause injury or  
death.  
Evacuation  
For field evacuation, use a rotary style  
vacuum pump capable of pulling a  
vacuum of 100 microns or less.  
When connecting the vacuum pump to a  
refrigeration system, it is important to  
manifold the pump to both the high and  
low side of the system. Follow the pump  
manufacturers directions.  
standards are addressed in ARI  
Standard 700.  
Use approved containment vessels and  
safety standards when shipping  
refrigerant containers.  
ƽ WARNING  
!
Do not use oxygen, acetylene, or  
air in place of refrigerant and dry  
nitrogen for leak testing. A  
violent explosion may result  
causing injury or death.  
ƽ CAUTION  
!
To minimize emissions while recovering  
refrigerant, use recycling equipment.  
Always attempt to use methods that  
will pull the lowest possible system  
vacuum while recovering and  
condensing refrigerant into  
Do not use a Meg ohm meter or  
apply power to the winding of a  
compressor while it is under a  
deep vacuum. This may damage  
the motor windings.  
containment.  
ƽ WARNING  
!
When leak checking with trace  
refrigerant and nitrogen, use HCFC22  
(R22) rather than CFC12 (R12) or any  
other fully halogenated refrigerants. Be  
aware of any new leak test methods  
which eliminate refrigerant as a trace  
gas.  
Refrigerant Charging  
Always use a pressure regulator,  
valves, and gauges to control  
drum and line pressures when  
pressure testing the system.  
Excessive pressures may cause  
line ruptures, equipment damage,  
or an explosion which may result  
in injury or death.  
After leak testing and evacuating the  
system, charge liquid refrigerant into the  
system through the liquid line valve. After  
some refrigerant has entered each  
circuit, charge gaseous refrigerant into  
the suction line shrader valve with the  
compressors running.  
When cleaning system components or  
parts, do not use CFC11 (R11) or CFC  
113 (R113). Refrigeration system clean-  
up methods using filters and dryers are  
recommended. Do not use solvents  
which have ozone depletion factors.  
Properly dispose of used materials.  
Take extra care to properly maintain all  
service equipment directly supporting  
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Maintenance  
To charge the system, complete the  
following procedure:  
ƽ WARNING  
ƽ WARNING  
!
!
Do not apply flame to the  
1. Charge liquid refrigerant into the liquid  
line service valve of each compressor  
circuit. The vacuum will draw some of  
the required refrigerant into the  
system. See Figure O-M-7 on page 105.  
2. Complete the charging process by  
charging gaseous refrigerant into the  
suction line shrader valve with the unit  
running. However, make sure that  
some refrigerant is present in each  
circuit before starting the compressors.  
The refrigerant container should be  
upright so that gaseous refrigerant is  
drawn off the top.  
Do not exceed 200 psig when  
leak testing the system. Damage  
to the unit could result, or an  
explosion may occur causing  
injury or death.  
refrigerant container to increase  
refrigerant pressure. Uncontrolled  
heat may cause excessive drum  
pressures and explosions,  
resulting in injury or death and  
equipment damage.  
In the event of required system repair,  
leak test the liquid line, evaporator coil,  
and suction line at pressures dictated by  
local codes, using the following  
guidelines.  
1. Charge enough refrigerant and dry  
weight. Use an accurate scale or  
charging cylinder to determine the  
exact weight of the refrigerant entering  
the system. Failure to use either a scale  
or a charging cylinder can lead to  
undercharging or overcharging  
resulting in unreliable operation.  
ƽ CAUTION  
!
Do not allow liquid refrigerant to  
come into contact with the skin.  
If it does, treat the injury as if the  
skin had been frostbitten or  
frozen. Slowly warm the affected  
area with lukewarm water and  
seek medical attention  
Note: Charge each circuit with R22. See  
Tables O-M-1 and O-M-2.  
ƽ CAUTION  
!
immediately.  
Do not allow liquid refrigerant to  
enter the suction line. Excessive  
liquid will damage the  
compressor.  
Table O-M-1. Water-Cooled Unit (SXWG) Refrigerant Charge.  
Unit Size  
Circuit A  
Circuit B  
Charge lbs. (kg)  
Charge lbs. (kg)  
SXWG 20  
SXWG 29  
25 (11.3)  
25 (11.3)  
SXWG 30  
SXWG 35  
27 (12.2)  
27 (12.2)  
25 (11.3)  
27 (12.2)  
Table O-M-2. Air-Cooled Unit (SXRG) Refrigerant Charge  
Unit Size  
Circuit 1  
Circuit 2  
Circuit 1  
Circuit 2  
Charge lbs. (kg)  
Charge lbs. (kg)  
SXRG 20  
SXRG 25, 32  
B-10 T  
B-10 T  
A-10 T  
A- 15 T  
36  
36  
36  
58  
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Maintenance  
Figure O-M-7. Typical water-cooled (SXWG) compressor section components.  
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Maintenance  
Inlet GuideVanes  
Perform the following procedure every  
six months for proper inlet guide vane  
operation:  
1. Spray all parts of guide vane assembly  
with WD40.  
2. Spray all steel parts of guide vane  
assembly with ZRC.  
On occasion, the inlet guide vane actuator  
or inlet guide vanes may need to be  
removed. For proper adjustment of inlet  
guide vanes and/or actuator, see Figure  
O-M-8.  
Note: Perform this procedure monthly if  
the unit is in a coastal area or corrosive  
environment.  
3. Spray hubs and moving parts with dry  
silicone lubricant (Mobil Mobilux 2, Shell  
alvonia 2, or equivalent).  
Figure O-M-8. Proper adjustment of inlet guide vanes.  
106  
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Owner  
Maintenance  
Coil Fin and External Cleaning  
7. Allow the unit to dry thoroughly before  
putting the system back into service.  
8. Straighten any coil fins that may be  
damaged with a fin rake.  
9. Replace all panels and parts and  
restore electrical power to the unit.  
10. Ensure that contaminated material  
does not contact other areas of the unit  
or building. Properly dispose of all  
contaminated materials and cleaning  
solutions.  
ƽ WARNING  
!
Keep coils clean to maintain maximum  
performance. For operation at its highest  
efficiency, clean the refrigerant coil often  
during periods of high cooling demand or  
when dirty conditions prevail. Clean the  
coil a minimum of once per year to  
prevent dirt buildup in the coil fins, where  
it may not be visible.  
Some chemical coil cleaning  
compounds are caustic or toxic.  
Use these substances only in  
accordance with the  
manufacturer’s instructions.  
Failure to do so may result in  
injury, death, or equipment  
damage.  
Remove large debris from the coils and  
straighten fins before cleaning. Remove  
filters before cleaning.  
Refrigerant Coils  
1. Disconnect all electrical power to the  
unit.  
2. Don the appropriate personal  
protective equipment (PPE).  
3. Gain access to the coil section of the  
unit (both sides).  
4. Use a soft brush to remove loose  
debris from both sides of the coil.  
5. Mix a high quality coil cleaning  
detergent with water according to the  
manufacturers instructions. If the  
detergent is strongly alkaline after  
mixing (pH 8.5 or higher), it must  
contain an inhibitor. Carefully follow the  
cleaning solution manufacturers  
instructions regarding product use.  
6. Place the mixed solution in a garden  
pump-up sprayer or high pressure  
sprayer. If using a high pressure  
sprayer note the following:  
If the refrigerant coil is installed back to  
back with the waterside economizer coil,  
use a cleaner that is acceptable for  
cleaning both types of coils.  
Clean refrigerant coils with cold water  
and detergent, or with one of the com-  
mercially available chemical coil clean-  
ers. Rinse coils thoroughly after cleaning.  
Inspecting and Cleaning Coils  
Economizer and evaporator coils are  
installed so the evaporator is directly  
behind the economizer.To clean between  
the coils, remove the sheet metal block  
off. Access the block off by removing the  
corner panels on the units left or right  
rear side.  
Coils become externally fouled as a result  
of normal operation. Dirt on the coil  
surface reduces its ability to transfer heat  
that can result in comfort problems,  
increased airflow resistance and thus  
increased operating energy costs. If the  
coil surface dirt becomes wet, which  
commonly occurs with cooling coils,  
microbial growth (mold) may result,  
causing unpleasant odors and serious  
health-related indoor air quality  
problems.  
ƽ CAUTION  
!
Caution: Do not clean the  
refrigerant coil with hot water or  
steam. The use of hot water or  
steam as a refrigerant coil-cleaner  
agent will cause high pressure  
inside the coil tubing and  
Inspect coils at least every six months or  
more frequently as dictated by operating  
experience. Cleaning frequently is  
dependent upon system operating hours,  
filter maintenance, and efficiency and dirt  
load. The suggested cleaning method is  
below:  
Maintain a minimum nozzle spray  
angle of 15 degrees  
subsequent damage to the coil.  
Spray perpendicular to the coil face  
Protect other areas of the unit and  
internal controls from contact with  
moisture or the cleaning solution  
Keep the nozzle at least 6 inches from  
the coil  
ƽ CAUTION  
!
Steam and Hot Water Coils  
1. Disconnect all electrical power to the  
unit.  
2. Don the appropriate personal  
protective equipment (PPE).  
3. Gain access to both sides of the coil  
section.  
4. Use a soft brush to remove loose  
debris from both sides of the coil.  
5. Use a steam cleaning machine, starting  
from the top of the coil and working  
downward. Clean the leaving air side of  
the coil first, then the entering air side.  
Use a block-off to prevent steam from  
blowing through the coil and into a dry  
section of the unit.  
Caution:To prevent damage to  
the unit, do not use acidic  
Do not exceed 600 psig  
chemical coil cleaners. Also, do  
not use alkaline chemical coil  
cleaners with a pH value greater  
then 8.5 (after mixing) without  
using an aluminum corrosion  
inhibitor in the cleaning solution.  
Draining the Coil  
ƽ CAUTION  
!
Failure to properly drain and vent  
coils when not in use during  
freezing temperatures may result  
in coil freeze-up damage.  
Drain plugs are in the piping below each  
coils supply and return header. Use these  
plugs to drain the coil and piping. When  
draining the coil, open the vents at the top  
of the supply and return headers.  
6. Repeat step 5 as necessary. Confirm  
that the drain line is open following  
completion of the cleaning process.  
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Owner  
Maintenance  
Also, a drain plug is at the bottom of the  
inlet condenser manifold and in the outlet  
pipe near the units left side. Remove  
these plugs to drain the condensers. Be  
sure to open the vent plugs at the top of  
the condenser inlet and outlet manifold.  
See Figure O-M-7 on page 105.  
2. Remove the condensers left side to  
expose the condenser tubes.  
3. Rotate a round brush through the tubes  
to loosen contaminant.  
4. Flush tubes with water to push the  
sludge out through the drain opening in  
the bottom of the supply header and  
the return pipe.  
When refilling the condenser/waterside  
economizer coil system with water,  
provide adequate water treatment to  
prevent the formation of scale or  
corrosion.  
5.To clean the economizer tubes, remove  
the cast iron header plates at the coils  
right end between the inlet and outlet  
headers (4-row coils; 2-row coils do not  
have cover plates at right end). Rotate  
round brush through tubes from left  
end to loosen contaminants. Flush  
tubes with water.  
ƽ CAUTION  
!
Failure to provide adequate water  
treatment in condenser systems  
may result in coil and condenser  
fouling or undue metal damage.  
6. Replace condenser end plates and  
clamps. The end plates must be  
centered when tightening the clamp.  
7. Replace coil headers with gaskets and  
torque bolts to 50 ft.-lb.  
8. Replace drain and vent plugs.  
Chemical Cleaning of Condenser and  
Economizer Coil  
Cleaning the Condenser  
Chemical cleaning removes scale  
deposits built up by minerals in the water.  
For a suitable chemical solution, consult a  
water treatment specialist. The  
condenser water circuit is composed of  
copper, steel, and cast iron.  
Note: Using improperly treated or un-  
treated water in this equipment may result  
in scaling, erosion, corrosion, algae, or  
slime. Engage the services of a qualified  
water treatment specialist to determine  
what treatment is advisable. The Trane  
Company warranty specifically excludes  
liability for corrosion, erosion, or deteriora-  
tion of Trane equipment. Trane assumes  
no responsibilities for the results of the  
use of untreated or improperly treated  
water, saline, or brackish water.  
The chemical supply house should  
approve or provide all materials used in  
the external circulating system, along  
with the quantity of cleaning material,  
duration of cleaning time, and safety  
precautions necessary for handling the  
cleaning agent.  
Condensing water contains minerals that  
collect on the condenser tube walls.  
Cooling towers also collect dust and  
foreign materials that deposit in the  
condenser tube. The formation of scale or  
sludge in the condenser is indicated by a  
decreased water flow, low temperature  
difference between inlet and outlet water,  
and abnormally high condensing tem-  
peratures.To maintain maximum  
condenser efficiency, the condenser must  
remain free of built-up scale and sludge.  
Clean the condenser either mechanically  
or chemically.  
Mechanical Cleaning of Condenser and  
Economizer Coils  
1.Turn off the condenser supply water.  
Remove drain plugs discussed in the  
Draining the Coilsection on page 94.  
108  
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Owner  
Maintenance  
Piping Components  
clip holds the paddle assembly in the  
switch body.  
3. Remove the wire retainer clip by  
reaching down past the paddle with a  
pair of slim nosed pliers and gripping  
the end of the wire. Pull up on the wire  
clip and remove it.  
4. After removing the wire clip, use the  
pliers to pull the paddle assembly out of  
the switch barrel. Clamp the pliers onto  
the end of the paddle and remove the  
paddle assembly. It will slide straight  
out.  
5. Clean the ferrous particulate from the  
magnet using a rag or tack cloth. The  
particulate is attracted to the magnet,  
so it is necessary to pull it off. It will not  
simply wipe off.  
Water Valves  
Water valves have a stern packing nut. If  
there is evidence of water leakage at the  
valve stem, proceed as follows:  
1. Remove actuator motor from support  
plate. (Remove four mount bolts)  
2. Remove shaft coupling.  
3.Torque the packing nut to 10-ft.-lbs. of  
torque.  
4. Replace shaft coupling.  
5. Replace actuator motor (reinstall the  
four mount bolts).  
Note: If it is necessary to remove the four  
valve body bolts for valve cleaning or  
service, torque to 45 ft-lb.  
6. After cleaning the magnet, replace the  
paddle assembly into the switch bodys  
barrel. However, it is important to  
position the paddle perpendicular to the  
arrow on the switchs side and place the  
paddles flat side facing the opposite  
direction or the arrow. Push the paddle  
assembly in until it hits the barrel cavity  
bottom.  
7. Place the spring clip into the switch  
barrel and push it down with a small,  
flat blade screwdriver until the spring  
clip engages the groove in the switch  
barrel.  
8.When replacing the paddle assembly,  
check the operation by pushing on the  
paddles flat side.The paddle should  
swing freely in the direction of the  
arrow.This action confirms that the  
paddle assembly is properly installed.  
9. Replace the switch into the unit piping  
using a good pipe thread sealer.Tighten  
the switch so that its final position has  
the arrow parallel to the water pipe and  
pointing toward the left end of the unit  
(arrow is pointing in the direction of the  
water flow).  
Flow Switch Maintenance  
Flow switches have a magnet on the  
vane assembly that attracts ferrous  
particulate may build up on the magnet to  
the point that the vane will wedge so that  
it will not operate.  
When the flow switch does not operate,  
remove and replace it or disassemble  
and clean it.  
Cleaning the Flow Switch  
If ferrous particulate contaminates tower  
water, the ferrous particles will cling to  
the magnet on the switch paddle  
assembly. A buildup of the ferrous  
particles over a period os time will cause  
the paddle to stick and cease to function  
properly.  
To avoid this problem, remove the switch  
and clean each time you clean the  
condensers, or clean as needed to keep  
the switch operational.  
To clean the paddle assembly, remove it  
following the procedure below:  
1. Remove the switch from the unit.  
2. The paddle assembly and wire retainer  
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Owner  
Maintenance  
Periodic Maintenance  
Checklists  
5. Check the liquid line sight glasses  
during operation. Bubbles in the sight  
glasses indicate a possible shortage of  
refrigerant or an obstruction in the  
liquid lines, such as dirty liquid line filter  
driers.  
6. Inspect filter driers for leaks, flow  
obstructions, or temperature drop  
across the filter drier. A noticeable  
temperature differential, such as 5 F, in  
the liquid line may indicate an  
obstruction. Replace the filter drier if it  
appears clogged.  
6. Inspect the inlet vane assembly and  
perform maintenance procedures in  
the IGV maintenance section on page  
106.  
Monthly Checklist  
The following check list provides the  
recommended maintenance schedule to  
keep the unit running efficiently.  
Note: Perform this procedure monthly if  
the unit is in a coastal or corrosive environ-  
ment.  
ƽ WARNING  
!
Annual Maintenance  
Check and tighten all set screws, bolts,  
locking collars and sheaves.  
1. Inspect, clean, and tighten all electrical  
connections.  
2. Visually inspect the entire unit casing  
for chips or corrosion. Remove rust or  
corrosion and repaint surfaces.  
3. Visually check for leaks in refrigerant  
piping.  
4. Inspect fan, motor, and control contacts.  
Replace badly worn or eroded contacts.  
5. Inspect the thermal expansion valve  
sensing bulbs for cleanliness, good  
contact with the suction line, and  
adequate insulation from ambient air.  
6. Verify the superheat setting is between  
12 and 17 F at the compressor.  
Disconnect power source and  
allow all rotating equipment to  
stop completely before servicing  
or inspecting the unit. Failure to  
do so may result in injury or  
death.  
7. Inspect the optional waterside  
economizer coil. Clean the coil to  
prevent airflow restrictions through the  
fins.  
8. Check and record operating pressures.  
1. Inspect unit air filters. Clean or replace  
if airflow is blocked or if filters are dirty.  
2. Inspect coils for excess moisture or  
icing. Icing on the coils may indicate low  
airflow supply, restricted airflow from  
dirty fins, evaporator frost protection  
sensor problems, or a shortage of  
refrigerant flowing through the coil.  
3. Check that condensate from the  
evaporator and economizer coils flows  
freely through the condensate piping,  
traps, drain pan, and drainage holes.  
Remove algae and or any airflow  
obstructions.  
Semi-Annual Maintenance  
1. Verify the fan motor is properly  
lubricated. Follow lubrication  
recommendations on the motor tag or  
nameplate. Contact the motor  
manufacturer for more information.  
2. Lubricate fan bearings. For best results,  
lubricate bearings during unit operation.  
Refer to the Fan Bearingssection on  
page 100.  
When checking operating pressures and  
conditions, establish the following  
nominal conditions for consistent mea-  
surements.  
1. Leaving air temperature greater than  
60 F.  
2. Entering air temperature between 80  
and 90 F  
3. Entering water temperature greater  
than 65 F  
4. Inlet vanes at least halfway open  
5. Compressors running at full load  
6. Drain the condensing water system  
and inspect it thoroughly for fouling.  
Clean the condensers if necessary.  
3. With power disconnected, manually  
rotate the fan wheel to check for  
obstructions in the housing or  
interference with fan blades or inlet  
guide vane option. Remove  
obstructions and debris. Center the fan  
wheel if necessary.  
4. Check the fan assembly sheave  
alignment.Tighten set screws to their  
proper torques.  
5. Check water valves for leakage at  
valve stem packing nut.  
4. Check the condition and tension of fan  
belts. Adjust tension if belts are floppy  
or squeal continually. Replace worn or  
fraying belts in matched sets.  
Note: Check and adjust belt tension at  
least twice daily the first days of new belt  
operation. Belt tension will rapidly de-  
crease until the belts are run in.  
110  
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Diagnostic  
Troubleshooting  
Troubleshooting  
System Checks  
Before proceeding with technical trouble  
charts or controls checkout, complete the  
follow system analysis:  
1. Measure actual supply voltage at the  
compressor and an motor terminals  
with the unit running.Voltage must be  
within the range listed on the motor  
nameplate. Phase imbalance must be  
less than 2.0 percent.  
2. Check all wiring and connections to be  
sure that they are intact, secure and  
properly routed. The as wired system  
diagrams are provided in the unit  
control panel.  
for additional operational info on the UCM  
system.  
Voltage Imbalance  
Voltage imbalance on three-phase  
systems can cause motor overheating  
and premature failure. Maximum  
allowable imbalance is 2.0 percent, and  
the readings used to determine it must be  
measured at the compressor terminals.  
Operating Procedures  
Install pressure gauges on the discharge  
and suction line access valves. When the  
unit has stabilized (after operating  
approximately 15 minutes at full load),  
record suction and discharge pressures.  
System malfunctions such as low airflow,  
line restrictions, incorrect refrigerant  
charge, malfunctioning of expansion  
valves, damaged compressors, and so  
onwill result in pressure variations  
which are outside the normal range.  
Voltage imbalance is defined as 100  
times the sum of the division of the three  
voltages from the average voltage. If, for  
example, the three measured voltages  
are 221, 230, 227, the average would be:  
(221+230+227) = 226 volts  
3
Note: If phasing at the main incoming  
power terminal is incorrect, switch two of  
the three incoming power leads. If a  
compressor has been replaced and the  
phase is changed at the compressor, it will  
run backwards and discharge pressure will  
be very low. To resolve incorrect compres-  
sor wire phasing, change phasing at the  
compressor.  
3. Check that all fuses are installed and  
properly sized.  
4. Inspect air filters and coils to bel sure  
that airflow to the unit is not restricted.  
5. Check the zone thermostat settings.  
6. Ensure that the fan is rotating in the  
proper direction. If phasing is wrong at  
the main power terminal block, the fan  
and compressors will not run.  
7. Inspect ductwork and duct connections  
for tightness.  
8. Inspect air temperature. Extremely  
warm return air will decrease the  
cooling capacity of the air conditioner.  
The percentage of voltage imbalance is  
then:  
100*(226-221) = 2.2%  
226  
In this example, 2.2 percent imbalance of  
more than 2.0 percent exists, be sure to  
check the voltage at the unit disconnect  
and terminal block switch. If an imbalance  
at the unit disconnect switch does not  
exceed 2.0 percent, the imbalance is  
caused by faulty wiring within the unit. Be  
sure to conduct a thorough inspection of  
the unit electrical wiring connections to  
locate the fault, and make any repairs  
necessary.  
It is important that pressures be mea-  
sured under stable and constant condi-  
tions in order for the readings to be  
useful. The unit mounted, remote  
mounted, or discharge air setpoint can be  
temporarily adjusted to simulate full load  
conditions.  
Some common unit problems and  
solutions are inTable D-T-1. A complete  
list of operating diagnostics begin on  
page 112. Reference the IntelliPak®  
Programming Guide, PKG-SVP01B-EN,  
Table D-T-1. Common Unit Problems and Solutions  
Problem  
Possible Cause  
Remedy  
Drain pan is overflowing  
Plugged drain line  
Unit not level  
Clean drain line  
Level unit  
Standing water in drain pan  
Wet interior insulation  
Unit not level  
Level unit  
Plugged drain line  
Clean drain line  
Coil face velocity too high  
Improper trap design  
Drain pan leaks/overflowing  
Condensation on surfaces  
Reduce fan speed  
Design trap per unit installation instructions  
Repair Leaks  
Insulate surfaces  
Excess Dirt in unit  
Missing filters  
Filter bypass  
Replace filters  
Reduce filter bypass  
Microbial growth (mold)  
Standing water in drain pan  
Moisture problems  
See Standing water in drain panabove  
See Wet interior insulationabove  
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Diagnostic  
Troubleshooting  
Diagnostics  
Diagnostics  
1, 2, 3, or 4  
Reset Required: (PAR) An automatic reset  
occurs after the CO2 sensor transducer  
input receives a signal that is within range  
for ten continuous seconds.  
Refer to the IntelliPak® Self-Contained  
Programming Guide, PKG-SVP01B-EN,  
for specific unit programming and  
troubleshooting information. In particular,  
reference the Service Mode Menuand  
Diagnostic Menusections in the  
programming guide. Refer to the  
following text for general diagnostic and  
troubleshooting procedures. Common  
diagnostics and troubleshooting  
Problem: The saturated condenser  
temperature input is out of range for  
circuit #1, 2, 3, or 4.  
Check: Sensor resistance should be  
between 830 ohms (200 F) and  
345.7Kohms (-40 F). If so, check field/unit  
wiring between sensor and MCM/SCM.  
Compressor Contactor Fail - Circuit 1, 2,  
3, or 4  
Problem: The compressor contactor for  
Ckt. 1, 2, 3, or 4 has malfunctioned.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the circuit  
#1, 2, 3, or 4 saturated condenser  
temperature sensor. (temp < -55 F or  
temp > 209 F).  
Reason for Diagnostic: The circuit  
compressor proving input is detected  
closed continuously for more than three  
seconds while neither compressor output  
on that circuit closes.  
procedures follow below.  
A
Auto Reset S/A Static Pressure Limit  
Problem: The supply air static pressure  
went too high.  
UCMs Reaction: A Lockout Ckt # 1, 2, 3,  
or 4request is issued to the compressor  
staging control function.  
UCMs Reaction: A "lockout ckt #1, 2, 3, or  
4 request is issued to the compressor  
staging control function.  
Reason for Diagnostic: The S/A static  
pressure exceeded the S/A static  
pressure limit setpoint for at least one  
second continuously.  
Reset Required: (PAR) An automatic reset  
occurs after the circuit 1, 2, 3, or 4  
condenser temp input returns to its  
allowable range within 10 seconds.  
Reset Required: (PMR) A manual reset is  
required after the disgnostic is set. It can  
be reset by the HI, Tracer Summit®, or by  
cycling power to the RTM.  
UCMs Reaction: A "supply air pressure  
shutdown" signal is sent to the following  
functions:  
D
CompressorTrip - Ckt 1, 2, 3, or 4  
Problem: The compressor ckt #1, 2, 3, or 4  
has tripped.  
Dirty Filter  
Problem:There is a dirty filter.  
a. Compressor staging control,  
b. Economizer actuator control,  
c. Heat operation,  
Reason for Diagnostic: The filter switch  
input on the RTM is closed for more than  
60 seconds continuously.  
d. Supply fan control,  
Reason for Diagnostic: The ckt #1, 2, 3, or  
4 compressor proving input is detected  
open continuously for more than 3  
seconds when either or both compressor  
outputs on that circuit energize (as  
described in the compressor protection  
function).  
e. IGV/VFD control,  
f. Exhaust fan control,  
g. Exhaust actuator control  
UCMs Reaction: An information only  
diagnostic is set.  
Reset Required: (PAR) An automatic reset  
occurs after the IGV close. The supply fan  
is not allowed to restart for 15 seconds  
after the diagnostic occurs. An auto reset  
will also occur if the unit cycles out of  
occupied mode and back.  
Reset Required: (INFO) An automatic  
reset occurs after the dirty filter input  
reopens for 60 continuous seconds.  
Reason for Diagnostic: The circuit  
compressor proving input is detected  
open continuously for more than 3  
seconds when either or both compressor  
outputs on that circuit energize (as  
described in the compressor protection  
function).  
E
C
ECEM Communications Failure  
Problem: The RTM has lost  
communication with the ECEM.  
CO2 Sensor Failure  
Problem: The VCM CO2 sensor input  
signal is out of range.  
UCMReaction: A lockout ckt #1, 2, 3, or  
4request is issued to the compressor  
staging control function.  
Check: Field/unit wiring between RTM  
and ECEM module.  
Check: Check field/unit wiring between  
sensor and VCM.  
Reset Required: (PMR) A manual reset is  
required after this diagnostic occurs. The  
diagnostic can be reset by the unit  
mounted HI module, Tracer Summit®, or  
by cycling power to the RTM.  
Reason for Diagnostic: The RTM has lost  
communication with the ECEM.  
UCMs Reaction: If the unit has the  
comparative enthalpy option, the  
economizer enable r.e. enthalpy function  
will revert to level 2 enthalpy  
comparison.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the CO2  
sensor transducer input.  
UCMs Reaction:The CO2 reset function  
disables.  
CondenserTemp Sensor Failure - Circuit  
112  
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Diagnostic  
Troubleshooting Diagnostics  
WSM, 01,18,05  
the demand limit commands issued to  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
b. Activation Conditions: temperature < -  
50 F or temperature > 209 F, and unit  
configured with water cooled  
the heat operation function (if  
applicable) and the compressor staging/  
chilled water cooling function will be  
cancelled.  
condenser and/or economizer  
c.Time to React: 10 sec <T < 20 sec  
d. DiagnosticText (Human Interface  
Display) ENTERINGWATERTEMP  
SENSOR FAIL”  
e. Actions to be Initiated: A Disable  
Water Side Economizerrequest is  
issued to Water Side Economizer  
Temperature Enable Function”  
f. Reset: An automatic reset occurs after  
the Entering WaterTemp. input returns to  
within range continuously for 10 seconds.  
b. If any of the GBAS setpoint control  
parameters are the HI-selected setpoint  
sources, then those setpoints will revert  
to the default HI setpoints.  
c. Any active GBAS output control  
parameters will be ignored.  
d. A failsafe function in the GBAS module  
will cause all GBAS outputs to be  
zeroed and deenergized.  
Emergency Stop  
Problem: The emergency top input is  
open.  
Reason for Diagnostic: An open circuit  
has occurred on the emergency stop  
input caused either by a high duct temp t-  
stat trip, or the opening of field-provided  
contacts, switch, etc.  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
UCMs Reaction: Off or close requests are  
issued as appropriate to the following  
functions;  
a. Compressor staging/chilled water  
cooling control  
b. Heat operation  
c. Supply fan control and proof of  
operation  
d. Exhaust fan control and proof of  
operation.  
e. Exhaust actuator control  
f. Outside air damper control  
g. OnVAV units, IGV/VFD control  
EvapTemp Sensor Failure - Circuit 1, 2, 3,  
or 4  
Problem: The evaporator temperature  
sensor (ckt #1, 2, 3, or 4) is out of range.  
H
Heat Failure  
Problem: The heat has failed.  
(Electric heat unit)Typically, this is  
because the electric heat section became  
too hot.  
Check: Sensor resistance should be  
between 830 ohms (200 F) and  
345.7Kohms (-40 F). If so, check field/unit  
wiring between sensor and MCM/SCM.  
Reason for Diagnostic: The heat fail input  
on the heat module was closed:  
a. for more than 80 seconds,  
b. for ten consecutive occurrances (each  
lasting five seconds or more) within a  
210 second period.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the circuit  
#1 evaporator temperature sensor input  
(temp < -55 F or temp > 209 F).  
Reset Required: (PMR) A manual reset is  
required after the emergency stop input  
recloses. The diagnostic can be reset by  
the HI,Tracer Summit®, or by cycling  
power to the RTM.  
UCMs Reaction:The coil frost protection  
function for the refrigeration circuit (#1,  
2,3, or 4) only is disabled.  
UCMs Reaction: An information only  
diagnostic is set.  
Entering Cond Water Temp Sensor Fail  
Problem:  
Reset Required: (PAR) An automatic reset  
occurs after the #1, 2, 3, or 4 evap temp  
input returns to its allowable range for 10  
seconds.  
Reset Required: (INFO) An automatic  
reset occurs after the heat fail input  
remains open for 210 seconds  
continuously.  
Activation Conditions: temperature < -50  
F or temperature > 209 F, and unit  
configured for water cooled  
condenser  
G
c.Time to React: 10 sec <T < 20 sec  
d. DiagnosticText (Human Interface  
Display) ENT COND WATERTEMP  
SENSOR FAIL”  
Heat Module Auxilliary Temperature  
Sensor Fail  
Problem: The heat mod aux temp sensor  
input is out of range.  
GBAS 0-5 VDC Module Comm Failure  
Problem: The RTM has lost  
communication with the GBAS module.  
e. Actions to be Initiated: A Lockout All  
Ckts request is issued to the  
Compressor Staging Function”  
f. Reset: An automatic reset occurs after  
the entering condenser water  
temperature input returns to within range  
continuously for 15 seconds.  
Check: Field/unit wiring between RTM  
and GBAS.  
Check: Sensor resistance should be  
between 830 ohms (200 F) and  
345.7Kohms (-40 F). If so, check field/unit  
wiring between sensor and heat module.  
Reason for Diagnostic: The RTM has lost  
communication with the GBAS module.  
Reason for Diagnostic: At least one  
enabled unit function has the heat  
module auxillary temperature input  
designated as its sensor, and the unit is  
reading a signal that is out of range for  
UCMs Reaction: The UCM will initiate the  
following actions;  
a. If the demand limit input was closed  
prior to the communications loss, then  
Entering Water Temp Sensor Fail  
a. Data used (module,packet,byte,bit):  
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Diagnostic  
Troubleshooting Diagnostics  
this input (temp < -55 F or temp > 209 F).  
the hydronic heat low air temp limit input  
closes for > 1 second, or if the chilled  
water low air temp limit trip input opens  
for > 1 second. On units with both  
hydronic heat and chilled water, both low  
air temp limit inputs are active, and the  
unit will respond in the same manner  
regardless of which input is used.  
went too high for the third consecutive  
time.  
Reason for Diagnostic: The auto reset  
supply air static pressure limit diagnostic  
has occurred for the third time while the  
unit is operating in occupied mode.  
UCMs Reaction:The functions that  
designated the heat module auxillary  
temperature input as their input are  
disabled.  
Reset Required: (PAR) An automatic reset  
occurs after the heat module auxillary  
temperature input returns to its allowable  
range for 10 seconds.  
UCMs Reaction: A "supply air pressure  
shutdown" signal is sent to the following  
functions;  
UCMs Reaction:The UCM will initiate the  
following actions;  
a. Compressor staging control,  
b. Economizer actuator control,  
c. Heat operation,  
a. An open all water valvesrequest is  
issued to the heat module function,  
causing any steam, hot water, or chilled  
water valves on the unit to open.  
b. An all heat offrequest is issued to  
the heat control function.  
c. A fan offrequest is sent to the supply  
fan control function.  
d. A close damperrequest is sent to  
the economizer actuator control  
function.  
Heat Module Comm Failure  
d. Supply fan control,  
Problem: The RTM has lost  
e. IGV/VFD control,  
communication with the heat module.  
f. Exhaust fan control  
g. Exhaust actuator control  
Check: Check field/unit wiring between  
RTM and heat module.  
Reset Required: (PMR) A manual reset is  
required and can be accomplished at the  
HI,Tracer Summit®, or by cycling power  
to the RTM.  
Reason for Diagnostic: The RTM has lost  
communication with the heat module.  
UCMs Reaction: An all heat offrequest  
Reset Required: (PMR) A manual reset is  
required after the low air temp limit trip  
condition clears. The diagnostic can be  
reset at the unit mounted human  
interface, byTracer Summit®, or by  
cycling power to the RTM.  
is sent to the heat operation function.  
MCM Communications Failure  
Problem: The RTM has lost  
communication with the MCM.  
If the unit has staged gas or electric heat,  
all heat module outputs will be zeroed  
and deenergized.  
Check: Check field/unit wiring between  
RTM and MCM.  
If the unit has hydronic heat or chilled  
water installed, the unit will turn off the  
supply fan and close the outside air  
damper upon the occurrance of a heat  
module comm failure. A failsafe function  
in the heat module will cause all water  
valves to be set to 100% to provide full  
water flow. Unless used for switching  
purposes (air handlers with chilled water  
and mod gas, or chilled water and  
hydronic heat) all binary outputs will be  
deenergized.  
Low Pressure Control Open - Circuit 1, 2,  
3, or 4  
Problem: The Low Pressure Control (LPC)  
for Ckt #1, 2, 3, or 4 is open.  
Reason for Diagnostic: The RTM has lost  
communications with the MCM.  
UCMs Reaction: A Lockoutrequest is  
sent to the compressor staging control  
function. And a failsafe function in the  
MCM will cause all MCM outputs to be  
zeroed and deenergized.  
Check: State of refrigerant charge for ckt  
#1, 2, 3, or 4.  
Reason for Diagnostic: The Ckt # 1 LPC  
input is detected open as described in the  
compressor protection function.  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
UCMs Reaction: A Lockout Ckt # 1, 2, 3,  
or 4request is issued to the compressor  
staging control function.  
Mode Input Failure  
Problem: The RTM mode input is out of  
range.  
Reset Required: (PMR) A manual reset is  
required anytime after the diagnostic is  
set. The diagnostic can be reset by the  
human interface,Tracer Summit®, or by  
cycling power to the RTM.  
L
Check: Sensor resistance should be  
between 1 ohm and 40 Kohms. If so,  
check field/unit wiring between sensor  
and RTM.  
Low Air Temp Limit Trip  
Problem: The low air temp limit has  
tripped. (Units with steam or hot water  
heating, or air handlers with chilled water  
cooling)  
Reason for Diagnostic: The mode input  
signal on the RTM is out of range  
(resistance < 1k ohm or resistance > 40k  
ohms).  
M
Reason for Diagnostic: A low air temp  
limit trip is detected continuously for  
more than one second. This can occur if  
Manual Reset SA Static Press Limit  
Problem: The supply air static pressure  
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Diagnostic  
Troubleshooting Diagnostics  
a signal that is out of range for the outside  
air humidity sensor (humidity < 5% or  
humidity > 100%).  
zone heating setpoint reverts to the  
default value.  
UCMs Reaction:The system mode  
reverts to the default (HI set) system  
mode.  
Reset Required: (PAR) an automatic reset  
occurs after the occupied zone heating  
setpoint input returns to its allowable  
range for 10 continuous seconds, or after  
a different occupied zone heating setpoint  
selection source is user-defined.  
UCMs Reaction:The economizer enable  
r.e enthalpy function reverts to dry-bulb  
temperature changeover (Level 1)  
control.  
Reset Required: (INFO) An automatic  
reset occurs after the mode input returns  
to its allowable range for 10 seconds.  
Reset Required: (PAR) An automatic reset  
occurs after the OA humidity input  
returns to its allowable range for 10  
seconds.  
N
R
NSB Panel ZoneTemperature Sensor  
Failure  
Problem: The NSB panel's zone temp  
sensor input is out of range. (This input is  
at the NSB panel, not on the unit itself).  
Return Air Humidity Sensor Failure  
Problem: On units with both airside  
economizer and comparative enthalpy  
installed, the return air humidity sensor  
input is out of range.  
O/A Temp. Sensor Failure  
Problem: The outside air temperature  
sensor input is out of range.  
Check: If have an external sensor  
Check: Check field/unit wiring between  
the sensor and ECEM.  
Check: Sensor resistance should be  
between 830 ohms (200 F)and 345.7  
Kohms (-40 F). If so, check field/unit wiring  
between sensor and RTM.  
connected to the NSB panel zone sensor  
input, then the internal NSB panel zone  
sensor should be disabled. Verify sensor  
resistance. If in valid range, check wiring  
between the sensor and NSB panel.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the return  
air humidity sensor (humidity < 5% or  
humidity > 100%).  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the outside  
air temperature input on the RTM (temp.  
< -55 F or temp > 209 F).  
NSB Panel Comm Failure  
Problem: The RTM has lost  
communications with the night setback  
panel (programmable zone sensor).  
UCMs Reaction:The economizer enable  
r.e. enthalpy function reverts to reference  
enthalpy changeover (Level 2) control.  
UCMs Reaction:These unit functions  
occur:  
low ambient compressor lockout  
disables  
O/A damper drives to minimum position  
onVAV units with S/A temp. reset type  
selected as O/A temp. reset, the reset  
type reverts to nonefor the duration  
of the failure  
Check: Field/unit wiring between RTM  
and NSB Panel.  
Reset Required: (PMR) An automatic  
reset occurs after the RA humidity input  
returns to its allowable range  
Reason for Diagnostic: The RTM has lost  
communication with the NSB panel.  
continuously for 10 seconds.  
UCMs Reaction:The unit reverts to the  
next lower priority mode switching  
source (typically the HI default mode). If  
the NSB panel zone sensor is the  
designated sensor source for any  
functions, those functions are disabled.  
Return Air Temp Sensor Failure  
Problem: On units with the comparative  
enthalpy option, the return air  
Reset Required: (PAR) an automatic reset  
occurs after the O/A temperature input  
returns to its allowable range.To prevent  
rapid cycling of the diagnostic, there is a  
10 second delay before the automatic  
reset.  
temperature sensor input is out of range.  
Check: Sensor resistance should be  
between 830 ohms (200 F) and  
345.7Kohms (-40 F). If so, check field/unit  
wiring between the sensor and ECEM.  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
Occupied Zone Heat Setpoint Failure  
Problem: The occupied zone heat setpoint  
input is out of range.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the return  
air humidity sensor (temp < -55 F or  
temp > 209 F).  
O
O/A Humidity Sensor Failure  
Problem: The outside air humidity sensor  
data is out of range.  
Reason for Diagnostic: The input  
designated as occupied zone heating  
setpoint source is out of range for the  
outside air temperature input on the RTM  
(temp. < 45 F or temp > 94 F).  
UCMs Reaction:The economizer enable  
r.e. enthalpy function reverts to reference  
enthalpy changeover (Level 2) control.  
Check: Check field/unit wiring between  
the sensor and RTM.  
Reset Required: (PAR) An automatic reset  
occurs after the RA temp input returns to  
UCMs Reaction:The active occupied  
Reason for Diagnostic: The unit is reading  
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Diagnostic  
Troubleshooting Diagnostics  
its allowable range continuously for 10  
seconds.  
Problem: The RTM zone temperature  
sensor input is out of range.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the space  
static pressure setpoint (input < 0.03 IWC  
or input > 0.20 IWC).  
Check: Sensor resistance should be  
between 830 ohms (200 F)and 345.7  
Kohms (-40 F). If so, check field/unit wiring  
between sensor and RTM.  
UCMs Reaction:The default space  
pressure setpoint will become the active  
space pressure setpoint.  
RTM Aux.Temp. Sensor Failure  
Problem: The RTM auxillary temperature  
sensor data is out of range.  
Reason for Diagnostic: At least one  
enabled unit function has the RTM zone  
temperature input designated as its  
sensor, and the unit is reading a signal  
that is out of range for this input (temp. < -  
55 F or temp > 150 F).  
Reset Required: (PAR) An automatic reset  
occurs after the designated space  
pressure setpoint source sends a signal  
within range for 10 continuous seconds,  
or after a different space pressure  
setpoint source is user-defined.  
Check: Sensor resistance should be  
between 830 ohms (200 F)and 345.7  
Kohms (-40 F). If so, check field/unit wiring  
between sensor and RTM.  
Reason for Diagnostic: At least one  
enabled unit function has the RTM  
auxillary temperature input designated  
as its sensor, and the unit is reading a  
signal that is out of range for this input  
(temp. < -55 F or temp > 209 F).  
UCMs Reaction:The functions with the  
RTM zone temperataure input deignated  
as their sensor are disabled.  
Supply Air Pressure Sensor Failure  
Problem: The supply air pressure sensor  
voltage input is out of range.  
Reset Required: (PAR) an automatic reset  
occurs after the designated zone  
temperature signal returns to its  
allowable range.To prevent rapid cycling  
of the diagnostic, there is a 10 second  
delay before the automatic reset.  
Check: Check field/unit wiring between  
the sensor and RTM.  
UCMs Reaction:The functions with the  
RTM auxillliary temperataure input  
deignated as their sensor are disabled.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the supply  
air pressure sensor voltage input (Input <  
40mV or Input > 4.75V)  
Reset Required: (PAR) an automatic reset  
occurs after the designated zone  
temperature signal returns to its  
allowable range.To prevent rapid cycling  
of the diagnostic, there is a 10 second  
delay before the automatic reset.  
S
SCM Communication Failure  
Problem: The RTM has lost  
communication with the SCM.  
UCMs Reaction:The IGVs will drive  
closed, and the following functions are  
disabled;  
a. SA pressure control  
b. SA static pressure limit  
Check: Check field/unit wiring between  
the RTM and SCM.  
RTM Data Storage Error  
Problem: There was a data transmission  
error.  
Reset Required: (PAR) An automatic reset  
occurs after the SA temp heating setpoint  
input returns to within range for 10  
continuous seconds, or after a different  
SA temp heating setopint selection  
source is user-defined.  
Reason for Diagnostic: The RTM has lost  
communication with the SCM.  
Check: This can be caused by an  
intermittant power loss.Turn the unit off  
for 1-2 minutes, then back on again. If  
diagnostic persists, then the RTM may  
need to be replaced.  
UCMs Reaction: A Lockoutrequest is  
sent to the compressor staging control  
function. A failsafe function in the SCM  
will cause all SCM outputs to be zeroed  
and deenergized.  
Supply Air Pressure Setpoint Failure  
Problem: The SA pressure input signal is  
out of range.  
Reason for Diagnostic: An error occurred  
while the RTM was writing data to its  
internal non-volitile memory (EEPROM).  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
Reason for Diagnostic: The SA pressure  
setpoint input is sending a signal that is  
out of range (Input < 1.0 IWC or Input > 4.3  
IWC)  
UCMs Reaction: An information only  
diagnostic will be displayed at the Human  
Interface.  
Space Static Press Setpt Failure  
Problem: The active space static pressure  
setpoint is out of range.  
Reset Required: (INFO) A manual reset  
may be made at the Human Interface, at  
Tracer Summit®, or by cycling power to  
the RTM.  
UCMs Reaction:The default SA pressure  
setpoint will become the active SA  
pressure setpoint.  
Check: Check setpoint value. Also, if  
space pressure setpoint source is GBAS,  
but this setpoint has not been assigned to  
any of the 4 analog inputs on GBAS, this  
message will occur.  
Reset Required: (PAR) An automatic reset  
occurs after the designated SA pressure  
setpoint source sends a signal within  
RTM Zone Sensor Failure  
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Troubleshooting Diagnostics  
range for 10 continuous seconds, or after  
a different SA pressure setpoint source is  
user-defined.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the supply  
air temperature input on the RTM (temp.  
< -55 F or temp > 209 F).  
g. IGV / VFD control  
Reset Required: (PMR) A manual reset is  
required anytime after the diagnostic is  
set. The diagnostic can be reset at the HI,  
Tracer Summit®, or by cycling power to  
the RTM.  
Supply AirTemp Cool Setpoint Fail  
Problem: The active supply air  
temperature cooling setpoint is out of  
range.  
UCMs Reaction:These unit functions are  
disabled:  
supply air tempering  
economizing  
supply air temperature low limit function  
(CV units)  
supply air temperature control heating  
and cooling functions (VAV units)  
Supply Fan VFD Bypass Enabled  
a. Data used (module,packet,byte,bit):  
RTM  
b. Activation conditions: supply fan VFD  
bypass has been activated and supply  
fan vfd bypass is installed.  
c.Time to React: 10 sec <T < 20 sec  
d. Diagnostic text (human interface  
display)  
SUPPLY FAN VFD BYPASS ENABLED”  
e. Actions to be Initiated: NONE  
f. Reset: The INFO diagnostic is cleared  
when the supply fan VFD bypass is  
deactivated.  
Reason for Diagnostic: The input  
designated as the SA temp cooling  
setpoint is out is out of range (temp < 35 F  
or temp > 95 F).  
Reset Required: (PAR) an automatic reset  
occurs after the designated S/A  
temperature input returns to its allowable  
range.To prevent rapid cycling of the  
diagnostic, there is a 10 second delay  
before the automatic reset.  
UCMs Reaction:The default HI-set SA  
temp cooling setpoint becomes the active  
SA temp cooling setpoint.  
Reset Required: (PAR) An automatic reset  
occurs after the SA temp cooling setpoint  
input returns to within range for 10  
continuous seconds, or after a different  
SA temp cooling setopint selection  
source is user-defined.  
Supply Fan Failure  
Problem: There is no supply airflow  
indication after the supply fan has been  
requested on.  
T
TCI Module Comm Failure  
Problem: The RTM has lost  
communication with the TCI.  
Supply AirTemp Heat Setpoint Fail  
Problem: The active supply air  
temperature cooling setpoint is out of  
range.  
Check: Check belts, linkages, etc. on the  
Supply Fan assembly. If these are ok,  
check field/unit wiring between RTM and  
supply fan. If the supply fan will run in  
service mode, then verify airflow proving  
switch and wiring.  
Check: Check field/unit wiring between  
RTM and TCI module.  
Reason for Diagnostic: The input  
designated as the SA temp heating  
setpoint is out is out of range (Temp < 35  
F orTemp > 185 F).  
Reason for Diagnostic: The RTM has lost  
communication with the TCI module.  
Reason for Diagnostic: The supply airflow  
input is detected OPEN for 40 continuous  
seconds during any period of time in  
which the supply fan binary output is ON.  
between 830 ohms (200 F) and  
345.7Kohms (-40 F). If so, check field/unit  
wiring between the sensor and MCM.  
UCMs Reaction: All active commands  
and setpoints provided byTracer  
Summit® through the TCI will be  
cancelled and/or ignored. And where  
Tracer Summit® has been designated as  
setpoint source, local HI default setpoints  
will be used.  
UCMs Reaction:The default HI-set SA  
temp heating setpoint becomes the  
active SA temp heating setpoint.  
Reset Required: (PAR) An automatic reset  
occurs after the SA temp heating setpoint  
input returns to within range for 10  
continuous seconds, or after a different  
SA temp heating setopint selection  
source is user-defined.  
This input is ignored for up to 5 minutes  
after the supply fan is first started, until  
airflow is first detected.  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
UCMs Reaction: OFF or Close”  
requests are issued as appropriate to the  
following functions;  
a. Compressor staging/chilled water  
control  
b. Heat operation  
Supply Air Temperature Failure  
Problem: The supply air temperature  
sensor input is out of range.  
Tracer Communications Failure  
Problem: The TCI has lost  
communications withTracer Summit®.  
c. Supply fan control and proof of  
operation.  
d. Exhaust fan control and proof of  
operation  
e. Exhaust actuator control  
f. Economizer actuator control  
Check: Sensor resistance should be  
between 830 ohms (200 F) and 345.7  
Kohms (-40 F). If so, check field/unit wiring  
between sensor and RTM.  
Check:Tracer Summit®(building control  
panel) is powered up and running  
properly. If so, check unit wiring between  
TCI andTracer Summit® (building control  
panel).  
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Diagnostic  
Troubleshooting Diagnostics  
designated as the unoccupied zone  
cooling setpoint source is out of range  
(Temp < 45 F orTemp > 94 F).  
compensation function if O/A flow  
compensation is enabled or set to the  
default minimum position function if O/A  
flow compensation is disabled or not  
available.  
Reset Required: (PAR) An automatic reset  
occurs after communication is restored.  
communications with the VOM.  
Reason for Diagnostic: The TCI has lost  
communications withTracer Summit® for  
> 15 minutes.  
UCMs Reaction:The active unoccupied  
zone cooling setpoint reverts to the  
default value.  
UCMs Reaction: All active commands  
and setpoints provided byTracer  
Summit® through the TCI will be  
cancelled and/or ignored. And where  
Tracer vSummit® has been designated as  
the setpoint source, local HI default  
setpoints are used.  
Reset Required: (PAR) An automatic reset  
occurs after the designated unoccupied  
zone cool setpoint input returns to its  
allowable range for 10 continuous  
seconds, or after the user defines a  
different, valid unoccupied zone cool  
setpoint selection source.  
Velocity Pressure Sensor Failure  
Problem: The velocity pressure input  
signal is out of range.  
Reset Required: (PAR) An automatic reset  
occurs after communication between  
Tracer Summit® and theTCI is restored.  
Check: Check field/unit wiring between  
sensor and VCM.  
Unoccupied Zone Heat Setpoint Failure  
Problem: The unoccupied zone heating  
setpoint input is out of range.  
Reason for Diagnostic: The unit is reading  
a signal that is out of range for the  
velocity pressure transducer input  
(during calibration: V < 40 mV or V > 420  
mV, during operation:V < 40 mV orV >  
0.75 V).  
U
Unit HI Communications Failure  
Problem: The RTM has lost  
communication with the unit mounted  
(local) human interface (HI).  
Reason for Diagnostic: The input  
designated as unoccupied zone heating  
setpoint source is out of range (temp < 45  
F or temp > 94 F).  
UCMs Reaction:The minimum airflow  
control function is disabled. The outside  
air damper minimum position function  
reverts to using the O/A flow  
Check: Field/unit wiring between RTM  
hand local HI.  
UCMs Reaction:The active unoccupied  
zone heating setpoint reverts to the  
default value.  
compensation function if O/A flow  
Reason for Diagnostic: The RTM has lost  
communication with the unit-mounted  
human interface.  
compensation is enabled or to the default  
minimum position function if O/A flow  
compensation is disabled or not available.  
Reset Required: (PAR) An automatic reset  
occurs after the designated unoccupied  
zone heat setpoint input returns to its  
allowable range for 10 continuous  
seconds, or after the user defines a  
different, valid unoccupied zone heating  
setpoint selection source.  
UCMs Reaction: A fail-safe function in the  
HI will cause the following sequence:  
a. disallow any interaction between the HI  
and the RTM (or any other modules),  
b. render all HI keystrokes ineffective  
c. cause the following message to display  
on the unit-mounted HI display: Local  
HI communications loss. Check comm  
link wiring between modules.If the  
unit has a remote HI option, then this  
diagnostic will display as any other  
automatic reset diagnostic.  
Reset Required: (PAR) An automatic reset  
occurs after the designated space  
pressure transducer sends a signal within  
range for 10 continuous seconds.  
VOM Communications Failure  
Problem: The RTM has lost  
communication with the VCM.  
V
VCM Communication Failure  
Problem: The RTM has lost  
communication with the VCM.  
Check: Field/unit wiring between RTM  
and VCM.  
Verify: Check field/unit wiring between  
RTM and VCM.  
Reset Required: (INFO) An automatic  
reset occurs after communication is  
restored between the RTM and the HI.  
When the failure screen clears, the  
general display restores to allow the HI to  
interact with the RTM again.  
Reason for Diagnostic: The RTM has lost  
communications with the VOM.  
Reason for Diagnostic: The RTM has lost  
communication with the VCM.  
UCMs Reaction: Ventilation override  
actions will not be allowed, and the VO  
Output relay will be deenergized.  
UCMs Reaction: All active commands  
and setpoints provided by the VCM are  
canceled and/or ignored. A fail-safe  
function in the VCM will cause all outputs  
to deenergize and/or set to zero. The  
outside air damper minimum position  
function will revert to using the O/A flow  
Reset Required: (PAR) An automatic reset  
occurs after communication has been  
restored.  
Unoccupied Zone Cool Setpoint Failure  
Problem: The unoccupied zone cooling  
setpoint input is out of range.  
Reason for Diagnostic: The input  
118  
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Diagnostic  
Troubleshooting Diagnostics  
W
·water side economizer is open 100%,  
· presetting of a Head Pressure Valve, or  
· demand for mechanical cooling.  
Unit must be: a. configured with water  
cooled condenser and/or water  
economizer and b. have water flow  
switch installed.  
c.Time to React: immediate  
WSM Communications Fail  
Problem: The RTM has lost  
communication with the WSM.  
Check: Field/unit wiring between RTM  
and WSM.  
Reason for Diagnostic: The RTM has lost  
communication with the WSM.  
UCMs Reaction:The UCM will react as if  
a freezestat has occurred by issuing:  
An All Heat Onor Mod Output Full  
Openrequest to Heat Control”  
A Fan offrequest to Supply Fan  
Control”  
A Close Damperrequest to  
Economizer Actuator Control”  
The water pump to turn on and position  
all water valves to provide maximum  
flow through all water source heat  
exchangers  
e. Actions to be Initiated: A Lockout All  
Cktsrequest is issued to the  
Compressor Staging Function”  
f. Reset: An automatic reset occurs after  
the Water Flow input returns to within  
range continuously for 3 seconds, the  
water pump is requested OFF, or the  
water flow switch becomes not installed.  
Z
Zone Cool Setpoint Failure  
Problem: The occupied zone cooling  
setpoint is out of range.  
Disables preheat function if WSM Mixed  
AirTemp Sensor is selected as Preheat  
Sensor  
Reason for Diagnostic: The input  
designated as occupied zone cooling  
setpoint source is out of range (temp. <  
45 F or temp > 94 F).  
Reset Required: An automatic reset  
occurs after one complete set of IPC  
packets is received.  
UCMs Reaction:The active occupied  
zone cooling setpoint reverts to the  
default occupied zone cooling setpoint.  
WSM Mixed AirTemp Sensor Fail  
b. Activation Conditions: temperature < -  
50 F or temperature > 209 F, and sensor  
is selected for use by Water Side  
EconomizerTemperature Enable  
Functionor Preheat Function”  
c.Time to React: 10 sec <T < 20 sec  
e. Actions to be Initiated: Water Side  
EconomizerTemperature Enable  
Functionuses Supply Air Cooling  
Setpoint instead of Mixed Air  
Reset Required: (PAR) an automatic reset  
occurs after the designated occupied  
zone CSP input returns to its allowable  
range for 10 continuous seconds, or after  
a different valid occupied zone CSP  
selection source is user-defined.  
Temperature. If Mixed AirTemperature is  
being used for Preheat Function, issue  
a Disablerequest to Preheat  
Function.  
f. Reset: An automatic reset occurs after  
the Mixed AirTemp. input returns to  
within range continuously for 10 seconds.  
Water Flow Fail  
a. Data used (module,packet,byte,bit):  
WSM, 01,19,05  
b. Activation Conditions: The water flow  
input is detected open ;  
1. at the end of precool water flow  
initiation state, or  
2. continuously for five minutes while:  
SCXG-SVX01B-EN  
119  
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Index  
Pair) Wiring 61  
Entering Cond Water Temp Sensor Fail  
113  
Entering Water Temp Sensor Fail 113  
Erase Button 67  
A
Communication Wiring 62  
Comparative Enthalpy Control 87  
Component Overview 63  
Compressor Circuit Breakers 89  
Compressor Contactor Fail 112  
Compressor Cycling 95  
Compressor Isolators 39  
Compressor Lead/Lag Operation 95  
Compressor Module 80  
Compressor Motor Winding Thermo-  
stats 89  
Compressor Safety Devices 96  
Compressor Stages 95  
Compressor Trip 112  
Compressors 95  
Condensate Drain Connections 34  
Condenser Connections 34  
Condenser Temp Sensor Failure 112  
condensing temperature rises above  
the lower limit 89  
Connecting to Tracer Summit 62  
Constant Volume Zone Sensor 55  
Constant Water Flow 84  
Control Options 5  
Control Power 37  
Control Sequences of Operation 91  
Cooling 93  
“After-Shipment” Accessory Model  
Number 8  
Air Filters 98  
Evacuation 103  
Evap Temp Sensor Failure 113  
Evaporator Coil Frost Protection 97  
Evaporator Temperature Sensor Frostat  
89  
EXHAUST sequence “C” 80  
Exhaust/Comparative Enthalpy Module  
81  
Air-Cooled Condensers 88  
Airside Economizer Installation 48  
Airside Economizer Interface 88  
Airside Economizer Interface with  
Comparative Enth 88  
Airside Economizer Option 87  
Airside Economizers with Traq Damper  
87  
Ambient Temperature and Humidity  
Limits 58  
Annual Maintenance 110  
Auto Changeover 94  
External Auto/Stop Switch 78  
External Unit Isolation 16  
F
Factory Mounted Time Clock 91  
Fan Bearings 100  
Fan Belt Tension 100  
Fan Button 67  
Fan Drive 99  
Fan shaft and motor sheave alignment  
99  
Field Supplied Occupied/Unoccupied  
Input on the RTM 91  
Filter Switch 90  
Flow Switch Maintenance 109  
FROSTAT 97  
Auto Reset S/A Static Pressure Limit  
112  
B
Basic Water Piping 84  
BAYSEN020 Icon Descriptions 72  
BAYSENS008 Description 50  
BAYSENS010 Description 52  
BAYSENS013 Description 52  
BAYSENS014 Description 52  
BAYSENS017B Description 51  
BAYSENS019 64  
BAYSENS019 Description 55  
BAYSENS019 Icon Descriptions 71  
BAYSENS019 Keypad and Display  
Explanation 64  
BAYSENS020 Keypad and Display  
Explanation 65  
BAYSENS020 Description 55  
BAYSENSO21 Description 51  
Brazing Procedures 36  
Cooling Capacity Percent 96  
Cooling Tower Interlock 80  
Cooling/Airside Economizer 93  
Cooling/Waterside Economizer 93  
Cycling Capacity Morning Warmup 91  
Full Capacity Morning Warmup 91  
G
GBAS 0-5 VDC Module Comm Failure  
113  
GBAS Analog Input Setpoints 83  
GBAS Analog Inputs 82  
GBAS Binary Input 82  
GBAS Binary Outputs 82  
GBAS Demand Limit Relay 82  
GBAS Diagnostics 82  
GBAS Input Voltage Corresponding  
Setpoint 83  
D
Day Button 67  
Daytime Warmup 94  
Diagnostics 112  
Dirty Filter 112  
Dirty Filter Sensor Option 86  
Draining the Coil 107  
Duct Connections 33  
Ductwork 63  
C
Cautions 59  
Changeover 94  
Chemical Cleaning of Condenser and  
Economizer Coil 108  
Cleaning the Condenser 108  
Cleaning the Flow Switch 109  
CO2 sensor 87  
General Waterside Recommendations:  
Cooling Towers 35  
Generic Building Automation System  
E
Module 82  
ECEM 81  
ECEM Communications Failure 112  
Electric Heat 94  
Electric Heat Coil Wiring Procedure 46  
Electric Heat Installation 46  
Emergency Stop 113  
H
CO2 Sensor Failure 112  
Head Pressure Control 89  
Heat Failure 113  
Heat Module 80  
Coil Fin and External Cleaning 107  
Common HVAC Acronyms 2  
Communication Link (Shielded Twisted  
Heat Module Auxilliary Temperature  
Emergency Stop Input 79  
120  
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Index  
Sensor Fail 113  
Heat Module Comm Failure 114  
HI 58, 80  
HI Location Recommendations 58  
High Duct Static Switch 90  
High Duct Temp Thermostat 90  
High Duct Temperature Thermostat 86  
high duct thermostat can be reset 90  
Holdtemp Button 67  
90, 97  
Occupied/Unoccupied Contacts 79  
Occupied/Unoccupied Inputs 78  
Occupied/Unoccupied Switching 91  
Operating Procedures 111  
Option Menu and Keypad Operation 69  
Optional Controls 5  
Low Ambient Control 89, 90  
Low Ambient Sensor 86  
Low Entering Air Protection Device 90  
Low Entering Air Temperature Sensor  
86  
Low Pressure Control 89  
Low Pressure Control Open 114  
Low Pressure Control Open 114  
Low Voltage (AC) Field Wiring  
Connections 61  
P
Periodic Maintenance Checklists 110  
Piping Components 109  
Plenum 41  
Human Interface 58  
Human Interface Module 80  
Human Interface Panel 5  
Hydronic Coil Installation 45  
Hydronic Heat 94  
Points List 77  
M
Pre-Installation Checklist 16  
Pre-Startup Checklist 63  
Pre-Startup Procedures 39  
Pressure Cutouts 96  
PRESSURIZE sequence “B” 80  
Program Button 66  
Program Menu 66  
Programmable Night Setback Zone  
Sensors 55  
Programmable Night Setback Zone  
Sensor Installatio 56  
Programming the Time Clock Option  
73  
PURGE sequence “D” 81  
PURGE with duct pressure control “E”  
81  
Maintenance Procedures 98  
Manual Override 73  
Manual Reset SA Static Press Limit  
114  
I
Icon Descriptions 71  
ICPB 61  
Initial Power-Up 66  
MCM 80  
MCM Communications Failure 114  
Measuring Belt Tension 100  
Mechanical Cleaning of Condenser and  
Economizer Coils 108  
Mechanical Cooling 94  
Minimum Outside Air Setpoint w/VCM  
Module and Traq 81  
Inlet Guide Vane 86  
Inlet Guide Vanes 106  
Input Devices and System Functions  
89  
Inspecting and Cleaning Coils 107  
Inspecting and Cleaning the Drain Pan  
98  
Inspecting and Cleaning the Fan 98  
Installation Preparation 10  
Installing the Remote Human Interface  
Panel 58  
Installing the Transducer 49  
Intelligent Copy 70  
Mode Button 67  
Mode Input Failure 114  
Model Number Description 6  
Monthly Checklist 110  
Morning Warmup 91  
Mounting Location 53  
Mounting the Remote Human Interface  
59  
R
Receiving 63  
Receiving and Handling 9  
Receiving Checklist 9  
Refrigerant Charge 104  
Refrigerant Coils 107  
IntelliPak Unit Controls 5  
Intermediate Water Piping 84  
Interprocessor Communication Bridge  
Module Wiring 61  
Mounting the Subbase 53  
MWU 91  
Refrigerant Emissions 102, 103  
Refrigerant Leak Testing 103  
Refrigerant Piping 36  
Refrigerant System 102  
Remote Human Interface Module  
Option 80  
Remote Human Interface Panel 58  
Remote Mounted Thermostat Option  
50  
Remote Mounted Thermostat Wiring  
50  
Remote Panel Indicator Signals From  
UCM to ZSM 70  
Remote Zone Sensor Options 51  
Reset based on outdoor air tempera-  
ture 94  
Interprocessor Communications Board  
80  
IPCB 80  
N
NSB Panel Comm Failure 115  
NSB Panel Zone Temperature Sensor  
Failure 115  
K
O
Keypad Lockout 67  
Keypad Operation for Temporary  
O/A Humidity Sensor Failure 115  
O/A Temp. Sensor Failure 115  
Occupied Sequence Of Operation 93  
Occupied Zone Heat Setpoint Failure  
115  
Occupied Zone Temperature - Cooling  
93  
Occupied Zone Temperature - Heating  
94  
Manual Override Men 67, 68  
L
Leak Test 36  
LEATPD 90  
Literature Change History 2  
Low Air Temp Limit Trip 114  
Low Ambient Compressor Lockout  
Reset based on zone temperature 94  
SCXG-SVX01B-EN  
121  
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Index  
Return Air Humidity Sensor Failure  
115  
Return Air Temp Sensor Failure 115  
Return Air Temperature Sensor 90  
RHI 58, 80  
Rigging and Handling 13  
Rigging and Unit Handling 12  
RTM Alarm Relay 78  
RTM Analog Outputs 78  
RTM Aux. Temp. Sensor Failure 116  
RTM Binary Outputs 78  
RTM Data Storage Error 116  
RTM Module Board 78  
RTM Remote Economizer Minimum  
Position 78  
Supply Air Pressure Sensor Failure 116  
Supply Air Pressure Setpoint Failure  
116  
Supply Air Setpoint Reset 94  
Supply Air Static Pressure Limit 86  
Supply Air Temp Cool Setpoint Fail 117  
Supply Air Temp Heat Setpoint Fail  
117  
Supply Air Temperature Control 93  
Supply Air Temperature Failure 117  
Supply Air Temperature Low Limit 90  
Supply Air Temperature Sensor 90  
Supply Air Tempering 94  
Supply Airflow Proving Switches 90  
Supply and Exhaust Fan Circuit Break-  
ers 90  
Unit Isolator Installation Procedure 40  
Unit Location 63  
Unit Mounting 63  
Unit Nameplate 5  
UNIT OFF sequence “A” 80  
Unit Protective Covers 39  
Unit Shipping 14  
Unit Start-Up Procedures 74  
Unit Startup 74  
Unit Vibration Isolator Option 40  
Unit Wiring Diagrams 37  
Units With Economizer 93  
Unoccupied 91  
Unoccupied Zone Cool Setpoint Failure  
118  
Unoccupied Zone Heat Setpoint Failure  
118  
Up and Down Button Arrows 67  
RTM Sensors 79  
RTM Zone Sensor Failure 116  
Supply Duct Static Pressure Control 79  
Supply Fan 99  
Supply Fan Circuit Breaker, Fuses, and  
Overloads 90  
Supply Fan Failure 117  
Using Intelligent Copy 70  
S
Saturated Condenser Temperature  
Sensors 89  
V
Supply Fan Isolators 39  
Variable Air Volume Zone Sensor 55  
Variable Frequency Drive 86  
Variable Frequency Drive Option 47  
Variable Water Flow 85  
SCM 80  
Supply Fan VFD Bypass Enabled 117  
Supply Power Wiring 37  
System Checks 111  
SCM Communication Failure 116  
Selection Procedures 38  
Semi-Annual Maintenance 110  
Service Access 11  
Service Valves 97  
Setting the Time 73  
Ship-Separate Accessories 9  
Ship-With Accessory Model Number  
Description 7  
Shipping Package 9  
Skid Removal 16  
Space Static Press Setpt Failure 116  
Special Note on Refrigeration Emis-  
sions 2  
Split-Apart Unit Assembly 14  
Standard Remote Sensor  
(BAYSENS017) 53  
Standard Two-Position Damper  
Interface 88  
Startup Log 75  
Static Pressure Transducer Installatio  
49  
Status/Annunciator Output 78  
Steam and Hot Water Coils 107  
Step Control 96  
suction pressure approaches 7 4 psig  
89  
suction pressure exceeds 22 4 psig  
89  
VAV Box Option 79  
T
VAV Changeover Contacts 78  
VAV Drive Max Output 78, 92  
VCM 81, 87  
VCM Communication Failure 118  
Velocity Pressure Sensor Failure 118  
Ventilation Control Module 81, 87  
Ventilation Override Module 80  
VFD 47, 86  
VFD Electrical Installation Procedure  
47  
VFD Mounting Requirements 47  
VFD with Bypass 86  
TCI 81  
TCI Module Comm Failure 117  
Temporary Manual Override 67  
Temporary Manual Override Run Mode  
68  
Temporary Override Run Mode 68  
Time and Day Settings 66  
Time Button 67  
Time Clock 91  
Time Clock Option 57  
Timeclock Installation 57  
Timeclock Installation Checklist 57  
Timed Override Activation 92  
Tracer Communications Failure 117  
Tracer Summit System 91  
Trane Communications Interface  
Module 81  
Voltage Imbalance 37, 111  
Voltage Range 37  
VOM 80  
VOM Communications Failure 118  
W
Transducer Location 49  
Wall Mounting the RHI Panel 59  
Warnings and Cautions 2  
Water Condenser Connection Sizes 84  
Water Flow Fail 119  
Water Flow Switch Option 84  
Water Piping 34  
U
Unit Airside Components 86  
Unit Components 4  
Unit Control Components 78  
Unit Control Module 5  
Water Piping Options 84  
Water Purge 84, 89  
Supply Air Fan 86  
Unit HI Communications Failure 118  
122  
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Index  
Water Temperature Requirements 35  
Water Valves 109  
Wiring the Remote Human Interface  
61  
Wiring the Timeclock 57  
WSM 80  
WSM Communications Fail 119  
WSM Mixed Air Temp Sensor Fail 119  
Water-Cooled Condensers 84  
Water-Cooled Unit Piping 63  
Waterside Components 84  
Waterside Economizer Flow Control  
84  
Waterside Economizer Installation  
Procedure 42  
Waterside Economizer Option 84  
Waterside Module 80  
Waterside Piping Arrangements 35  
Wiring 53  
Wiring the Remote Air-cooled CCRC  
and SCRG 50  
Z
Zone Cool Setpoint Failure 119  
Zone Sensor Installation 53  
Zone Sensor Maximum Lengths and  
Wire Size 53  
Zone Temperature - Heating 94  
Zone Temperature Control 93  
SCXG-SVX01B-EN  
123  
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Literature Order Number  
File Number  
SCXG-SVX01B-EN  
PL-UN-SCXF-SVX01B-EN 700  
SCXG-SVX01A-EN  
TheTrane Company  
Supersedes  
A Division of American Standard Inc.  
www.trane.com  
Stocking Location  
LaCrosse - Inland  
For more information contact  
your local district office or  
e-mail us at [email protected]  
SinceTheTrane Company has a policy of continuous product improvement, it reserves the right to change design  
and specifications without notice.  
An American Standard Company  
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