38YCX—50 Hz
Heat Pump—Outdoor Section
Installation and Start-Up Instructions
NOTE: Read the entire instruction manual before starting the
installation.
This symbol → indicates a change since the last issue.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause personal injury or property damage.
Consult a qualified installer, service agency, or your distributor or
branch for information or assistance. The qualified installer or
agency must use factory-authorized kits or accessories when
modifying this product. Refer to the individual instructions pack-
aged with the kits or accessories when installing.
IP24
Follow all safety codes. Wear safety glasses and work gloves. Use
quenching cloth for brazing operations. Have fire extinguisher
available. Read these instructions thoroughly and follow all
warnings or cautions attached to the unit. Consult local building
codes and the national electric codes for special installation
requirements.
Recognize safety information. This is the safety-alert symbol
When you see this symbol on the unit or in instructions and
manuals, be alert to the potential for personal injury.
.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards which
could result in personal injury or death. CAUTION is used to
identify unsafe practices which would result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability,
or operation.
A97005
Fig. 1—Model 38YCX
When installing, allow sufficient space for airflow clearance,
wiring, refrigerant piping, and service. Allow 30-in. (762mm)
clearance to service end of unit and 48 in. (1219mm) above unit.
For proper airflow, a 6-in. (152mm) clearance on 1 side of unit and
12 in. (305mm) on all remaining sides must be maintained.
Maintain a distance of 24 in. (610mm) between units. Position so
water, snow, or ice from roof or eaves cannot fall directly on unit.
Before installing, modifying, or servicing system, main elec-
trical disconnect switch must be in the OFF position. There
may be more than 1 disconnect switch. Lock out and tag
switch with a suitable warning label. Electrical shock can
cause personal injury or death.
On rooftop applications, locate unit at least 6 in. (152mm) above
roof surface. Place unit above a load-bearing wall and isolate unit
and tubing set from structure.
Arrange supporting members to adequately support unit and
minimize transmission of vibration to building. Consult local
codes governing rooftop applications.
INSTALLATION
Step 1—Check Equipment and Job Site
Step 3—Elevate Unit
UNPACK UNIT — Move to final location. Remove carton taking
care not to damage unit.
INSPECT EQUIPMENT — File claim with shipping company
prior to installation if shipment is damaged or incomplete. Locate
unit rating plate on unit corner panel. (See Fig. 2.) It contains
information needed to properly install unit. Check rating plate to
be sure unit matches job specifications.
Accumulation of water and ice in base pan may cause
equipment damage.
In areas where prolonged freezing temperatures are encountered,
elevate unit per local climate and code requirements to provide
clearance above estimated snowfall level and ensure adequate
drainage of unit. (See Fig. 3.)
Step 2—Install on a Solid, Level Mounting Pad
If conditions or local codes require the unit be attached to pad, tie
down bolts should be used and fastened through knockouts
provided in unit base pan. Refer to unit mounting pattern in Fig. 2
to determine base pan size and knockout hole location.
Step 4—Replace Indoor AccuRater® Piston (if required)
Check indoor coil piston to see if it matches the required piston
shown on outdoor unit rating plate. (See Fig. 2.) If it does not
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 5a 5a
1
4
PC 101
Catalog No. 003-880
Printed in U.S.A.
Form 38YCX-C3SI
Pg 1
2-02
Replaces: 38YCX-C2SI
Download from Www.Somanuals.com. All Manuals Search And Download.
Table 1—Refrigerant Connections and Recommended Liquid and Vapor Tube Diameters
LIQUID
VAPOR
UNIT SIZE
Connection Dia.
In. mm
Tube Dia.
mm
Connection DIia.
Vapor Dia.
In.
3/8
3/8
3/8
3/8
In.
mm
In.
5/8
mm
024
036
048
060
3/8
3/8
3/8
3/8
9.53
9.53
9.53
9.53
9.53
9.53
9.53
9.53
5/8
3/4
7/8
7/8
15.88
19.05
22.23
22.23
15.88
19.05
22.23
28.58
3/4
7/8
1-1/8
NOTES: 1. Tube diameters are for lengths up to 50 ft (15.24m). For tubing lengths greater than 50 ft (15.24m), consult Long-Line Application Guideline.
2. Do not apply capillary tube indoor coils to these units.
NOTE:Avoid contact between tubing and structure.
OUTDOOR WALL
CAULK
INDOOR WALL
To prevent compressor damage DO NOT bury more than 36
in. of refrigerant tubing. If ANY tubing is buried, provide 6
in. vertical rise at service valve.
LIQUID TUBE
To prevent damage to unit or service valves observe the
following:
• Use a brazing shield.
• Wrap service valves with wet cloth or use a heat sink
material.
VAPOR TUBE
JOIST
INSULATION
THROUGH THE WALL
Outdoor units may be connected to indoor section using accessory
tubing package or field-supplied refrigerant grade tubing of correct
size and condition. For tubing requirements beyond 50 ft (15.24m),
consult Long-Line Application Guideline which is available from
your local distributor.
HANGER STRAP
(AROUND VAPOR
TUBE ONLY)
INSULATION
VAPOR TUBE
NOTE: In some cases noise in the living area has been traced to
gas pulsations from improper installation of equipment.
INSTALLATION RECOMMENDATIONS
1. Locate unit away from windows.
1″ MIN
2. Ensure that vapor and liquid tube diameters are appropriate to
capacity of unit. (See Table 1.)
(25 mm)
LIQUID TUBE
SUSPENSION
3. Run refrigerant tubes as directly as possible by avoiding
unnecessary turns and bends.
A94330
4. Leave some slack between structure and unit to absorb
vibration.
Fig. 4—Piping Installation
5. When passing refrigerant tubes through the wall, seal opening
with RTV or other pliable silicon-based caulk. (See Fig. 4.)
PISTON BODY
6. Avoid direct tubing contact with water pipes, ductwork, floor
joists, wall studs, floors, and walls.
7. Do not suspend refrigerant tubing from joists and studs with a
rigid wire or strap which comes in direct contact with tubing.
(See Fig. 4.)
8. Ensure that tubing insulation is pliable and completely sur-
rounds vapor tube.
PISTON
9. When necessary, use hangar straps which are 1 in. (25mm)
wide and conform to shape of tubing insulation. (See Fig. 4.)
PISTON RETAINER
10. Isolate hangar straps from insulation by using metal sleeves
bent to conform to shape of insulation.
SWEAT/FLARE ADAPTER
If refrigerant tubes or indoor coil is exposed to atmosphere, it must
be evacuated to 500 microns to eliminate contamination and
moisture in the system.
A94029
Fig. 5—Service Valve with Sweat Adapter Tube
OUTDOOR UNIT CONNECTED TO FACTORY-APPROVED
INDOOR UNIT — Outdoor unit contains correct system refriger-
ant charge for operation with indoor unit of same size when
connected by 15 ft (4.55m) of field-supplied or factory-accessory
tubing. Check refrigerant charge for maximum efficiency.
3
Download from Www.Somanuals.com. All Manuals Search And Download.
REFRIGERANT TUBING — Connect tubing to fittings on out-
door unit vapor and liquid service valves. (See Fig. 2 and 5.)
The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault
should occur. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing
electrical codes. Failure to follow this warning can result in an
electric shock, fire, or death.
SWEAT CONNECTION — Use refrigerant grade tubing. Service
valves are closed from factory and ready for brazing. After
wrapping service valve with a wet cloth, tubing set can be brazed
to service valve using either silver bearing or non-silver bearing
brazing material. Consult local code requirements. Refrigerant
tubing and indoor coil are now ready for leak testing. This check
should include all field and factory joints.
NOTE: Use No. 18 AWG (American Wire Gage) color-coded,
insulated (35°C minimum) wires. If thermostat is located more
than 100 ft (30.5m) from unit (as measured along the control
voltage wires), use No. 16 AWG color-coded wires to avoid
excessive voltage drop.
Step 6—Make Electrical Connections
To avoid personal injury or death, do not supply power to unit
with compressor terminal box cover removed.
CONNECT CONTROL WIRING — Route 24-v control wires
through control wiring grommet and connect leads to control
wiring terminal board. (See Fig. 7.)
Be sure field wiring complies with local and national fire, safety,
and electrical codes, and voltage to system is within limits shown
on unit rating plate. Contact local power company for correction of
improper voltage. See unit rating plate for recommended circuit
protection device.
Use furnace transformer, fan coil transformer, or accessory trans-
former for control power, 24-v/40-va minimum.
NOTE: Use of available 24-v accessories may exceed the mini-
mum 40-va power requirement. Determine total transformer load-
ing and increase the transformer capacity or split the load with an
accessory transformer as required.
NOTE: Operation of unit on improper line voltage constitutes
abuse and could affect unit reliability. See unit rating plate. Do not
install unit in system where voltage may fluctuate above or below
permissible limits.
NOTE: The defrost timer is factory set for 90-minute cycles. The
timer can be field set for 30- and 50-minute cycles depending on
defrost conditions in your geographic location.
NOTE: Use copper wire only between disconnect switch and
unit.
Step 7—Compressor Crankcase Heater
NOTE: Install branch circuit disconnect per local codes to handle
unit starting current. Locate disconnect within sight from and
readily accessible from unit per local codes.
When equipped with a crankcase heater, energize heater a mini-
mum of 24 hr before starting unit. To energize heater only, set
thermostat to OFF and close electrical disconnect to outdoor unit.
ROUTE GROUND AND POWER WIRES — Remove access
panel and control box cover to gain access to unit wiring. Extend
wires from disconnect through power wiring hole provided and
into unit control box. (See Fig. 2.) Size wires per local codes but
not smaller than minimum wire size shown on unit rating plate.
A crankcase heater is required if the refrigerant tubing is longer
than 50 ft.
Step 8—Install Electrical Accessories
Refer to the individual instructions packaged with the kits or
accessories when installing.
CONNECT GROUND AND POWER WIRES — Connect ground
wire to ground connection in control box for safety. Connect
power wiring to contactor as shown in Fig. 6.
Step 9—Start-up and Check Charge
DISCONNECT PER
IEC AND/OR
To prevent compressor damage or personal injury, observe
the following:
• Do not overcharge system with refrigerant.
• Do not operate unit in a vacuum or at negative pressure.
• Do not disable low-pressure switch
In scroll compressor applications:
LOCAL CODES
FIELD POWER
CONTACTOR
L1
WIRING
L1
L2/N
L3
N FOR 1-PHASE ONLY
3-PHASE ONLY
• Dome temperatures may be hot.
L2/N
L3
To prevent personal injury wear safety glasses, protective
clothing, and gloves when handling refrigerant and observe
the following:
PE
PE
• Back seating service valves are not equipped with Schrader
valves. Fully back seat (counter clockwise) valve stem before
removing gage port cap.
GROUND
LUG
• Front seating service valves are equipped with Schrader
valves.
A96650
Fig. 6—Line Power Connections
4
Download from Www.Somanuals.com. All Manuals Search And Download.
FB4ASX
FB4ASX
HEAT PUMP
R
HEAT PUMP
R
FAN COIL
FAN COIL
THERMOSTAT
THERMOSTAT
R
G
C
R
G
R
G
C
R
G
C
C
C
C
W2
E
W2
W2
W2
E
W2
E
W2
ODTS
BLU
L
L
W3
O
Y
O
Y
O
Y
O
Y
SYSTEMS WITH ONE
OUTDOOR THERMOSTAT
SYSTEMS WITHOUT
OUTDOOR THERMOSTAT
A97053
A97054
FB4ASX
FAN COIL
THERMOSTAT
HEAT PUMP
R
R
G
R
G
C
C
C
W2
L
W2
W2
ODTS1
BLU
VIO
W3
E
E
ODTS2
O
Y
O
Y
C
1
4
7
C
9
6
3
EMERGENCY HEAT RELAY
SYSTEMS WITH TWO
OUTDOOR THERMOSTATS
A97052
Fig. 7—24-v Control Circuit Connections
5
Download from Www.Somanuals.com. All Manuals Search And Download.
Do not vent refrigerant to atmosphere. Recover during system
repair or final unit disposal.
1. If equipped with a crankcase heater, energize a minimum of
24 hr before starting unit. To energize heater only, set
thermostat OFF and close electrical disconnect to outdoor
unit.
2. Fully open liquid and vapor service valves.
3. Unit is shipped with valve stem(s) front seated and caps
installed. Replace stem caps after system is opened to refrig-
erant flow. Replace caps finger tight and tighten additional 1/6
turn using a backup wrench on valve body flats to prevent
distortion of sheet metal.
A00010
Fig. 8—Phase Monitor Control
4. Close electrical disconnects to energize system.
5. Set room thermostat at desired temperature.
Table 2—Phase Monitor LED Indicators
LED
OFF
STATUS
6. Set room thermostat to HEAT or COOL and fan to ON or
AUTO mode, as desired. Operate unit for 15 minutes. Check
system refrigerant charge.
No call for compressor
operation
FLASHING
ON
Reversed phase
Normal
7. Factory charge is shown on unit rating plate. Adjust charge in
cooling mode by following procedure shown in charging
table. Check charge in heating mode by following procedure
shown on heating check chart. Both are located on unit.
Should the temperature continue to fall, R-W2 is made through the
second-stage room thermostat bulb. Circuit R-W2 energizes a
sequencer, bringing on the first bank supplemental electric heat
and providing electrical potential to the second heater sequencer (if
used). If outdoor temperature falls below the setting of the outdoor
thermostat (field-installed option), contacts close to complete the
circuit and bring on the second bank of supplemental electric heat.
• 3-phase scroll compressors are rotation sensitive.
• A flashing LED on phase monitor indicates reverse rotation.
(See Fig. 8 and Table 2.)
• This will not allow contactor to be energized.
• Disconnect power to unit and interchange 2 field wiring
leads on unit contactor.
When the thermostat is satisfied, its contacts open, de-energizing
contactor and sequencer. All heaters and motors should stop.
→ Quiet Shift
SEQUENCE OF OPERATION — With power supplied to indoor
and outdoor units, transformer is energized. Defrost control board
is equipped with 5-minute lockout timer which may be initiated
upon any interruption of power.
Quiet Shift is a field-selectable defrost mode, which will eliminate
occasional noise that could be heard at the start of the defrost cycle
and restarting of heating cycle. It is selected by placing DIP switch
3 (on defrost board) in ON position.
Cooling
When Quiet Shift switch is placed in ON position, and a defrost is
initiated, the following sequence of operation will occur. Revers-
ing valve will energize, compressor will turn off for 30 sec, then
turn back on to complete defrost. At the start of heating cycle after
conclusion of defrost mode, reversing valve will de-energize, the
compressor will turn off for another 30 sec, and the fan will turn
off for 40 sec, before starting in the heating mode.
On a call for cooling, the thermostat makes circuits R-O, R-Y, and
R-G. Circuit R-O energizes reversing valve, switching it to cooling
position. On three phase models with scroll compressors, the units
are equipped with a phase monitor to detect if the incoming power
is correctly phased for compressor operation. (See Fig. 8 and Table
2.) If phasing is correct, circuit R-Y energizes contactor, starting
outdoor fan motor and compressor circuit. R-G energizes indoor
unit blower relay, starting indoor blower motor on high speed.
→ Defrost
The defrost control is a time/temperature control which includes a
field-selectable time period (DIP switch 1 and 2 on the board)
between defrost cycles of 30, 60, 90, or 120 minutes (factory set at
90 minutes).
NOTE: If the phasing is incorrect, the contactor will not be
energized. To correct the phasing, interchange any two of the three
power connections on the field side.
When thermostat is satisfied, its contacts open, de-energizing
contactor and blower relay. Compressor and motors stop.
To initiate a forced defrost, two options are available depending on
the status of the defrost thermostat.
NOTE: If indoor unit is equipped with a time-delay relay circuit,
the blower runs an additional 90 sec to increase system efficiency.
If defrost thermostat is closed, speedup pins (J1) must be shorted
by placing a flat head screwdriver in between for 5 sec and
releasing, to observe a complete defrost cycle. When the Quiet
Shift switch is selected, compressor will be turned off for two 30
sec intervals during this complete defrost cycle as explained
previously. When Quiet Shift switch is in factory default OFF
position, a normal and complete defrost cycle will be observed.
Heating
On a call for heating, the thermostat makes circuits R-Y and R-G.
If phasing is correct, circuit R-Y energizes contactor, starting
outdoor fan motor and compressor. Circuit R-G energizes indoor
blower relay, starting blower motor on high speed.
6
Download from Www.Somanuals.com. All Manuals Search And Download.
If defrost thermostat is in open position, and speedup pins are
shorted (with a flat head screwdriver) for 5 sec and released, a
short defrost cycle will be observed (actual length is dependent
upon the selected Quiet Shift position). When Quiet Shift switch is
in ON position, the length of defrost is 1 minute (30 sec
compressor off period followed by 30 sec of defrost with com-
pressor operation). On return to heating operation, compressor will
again turn off for an additional 30 sec and the fan for 40 sec. When
the Quiet Shift is in OFF position, only a brief 30 sec cycle will be
observed.
If it is desirable to observe a complete defrost in warmer weather,
the thermostat must be closed as follows:
1. Turn off power to outdoor unit.
CESO130076–00
2. Disconnect outdoor fan motor lead from OF2 on control board
(See Fig. 9.) Tape to prevent grounding.
Speedup
Pins
Quiet
Shift
Defrost interval
DIP switches
A99442
3. Restart unit in heating mode, allowing frost to accumulate on
outdoor coil.
Fig. 9—Defrost Control
CARE AND MAINTENANCE
4. After a few minutes in heating mode, liquid line temperature
should drop below closing point of defrost thermostat (ap-
proximately 30°F).
For continuing high performance and to minimize possible equip-
ment failure, periodic maintenance must be performed on this
equipment.
NOTE: Unit will remain in defrost until defrost thermostat
reopens at approximately 80°F coil temperature at liquid line or
remainder of defrost cycle time.
Leave User’s Manual with owner. Explain system operation and
periodic maintenance requirements outlined in manual. Frequency
of maintenance may vary depending upon geographic areas, such
as coastal applications.
5. Turn off power to outdoor and reconnect fan motor lead to
OF2 on control board after above forced defrost cycle.
7
Download from Www.Somanuals.com. All Manuals Search And Download.
Copyright 2002 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
38ycxc3si
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 5a 5a
1
4
PC 101
Catalog No. 003-880
Printed in U.S.A.
Form 38YCX-C3SI
Pg 8
2-02
Replaces: 38YCX-C2SI
Download from Www.Somanuals.com. All Manuals Search And Download.
|