38CKC(Q), 38CMC, 38BRC
Split-System Air Conditioner
Installation and Start-Up Instructions
NOTE: Read the entire instruction manual before starting the
installation.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, 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
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have fire extinguisher available. Read these instructions thor-
oughly and follow all warnings or cautions included in literature
and attached to the unit. Consult local building codes and National
Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety-alert symbol
.
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
A97005
Fig. 1—Split-System Air Conditioner
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.
7. Do not suspend refrigerant tubing from joists and studs with a
rigid wire or strap which comes in direct contact with the
tubing. (See Fig. 2.)
8. Ensure that tubing insulation is pliable and completely sur-
rounds vapor tube.
9. When necessary, use hanger straps which are 1 in. wide and
conform to shape of tubing insulation. (See Fig. 2.)
10. Isolate hanger straps from insulation by using metal sleeves
bent to conform to shape of insulation.
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.
When outdoor unit is connected to factory-approved indoor unit,
outdoor unit contains system refrigerant charge for operation with
factory-approved indoor unit of the same size when connected by
15 ft of field-supplied tubing. For proper unit operation, check
refrigerant charge using charging information located on control
box cover.
INSTALLATION RECOMMENDATIONS
NOTE: In some cases noise in the living area has been traced to
gas pulsations from improper installation of equipment.
INSTALLATION
1. Locate unit away from windows.
Step 1—Check Equipment and Jobsite
2. Ensure that vapor and liquid tube diameters are appropriate to
capacity of unit. (See Model Specific Instructions for proper
tube sizing.)
INSPECT EQUIPMENT — If shipment is damaged or incom-
plete, file claim with shipping company prior to installation.
Locate unit rating plate on unit service panel. It contains informa-
tion needed to properly install unit. Check rating plate to be sure
unit matches job specifications.
3. Run refrigerant tubes as directly as possible by avoiding
unnecessary turns and bends.
4. Leave some slack between structure and unit to absorb
vibration.
Step 2—Install on a Solid, Level Mounting Pad
5. When passing refrigerant tubes through the wall, seal opening
with RTV or other pliable silicon-based caulk. (See Fig. 2.)
If conditions or local codes require the unit be attached to pad, use
tiedown bolts to fasten through knockouts provided in unit base
pan. Refer to Fig. 3 for pad dimensions and dimensions needed to
mount unit to pad.
6. Avoid direct tubing contact with water pipes, ductwork, floor
joists, wall studs, floors, and walls.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 3a 2a
1
4
PC 101
Catalog No. 533-840
Printed in U.S.A.
Form 38BRC-1SI
Pg 1
2-97
Replaces: New
AIR DISCHARGE
If undersized, damaged, or elliptically shaped tubing is used
when making connection, leaks could result.
3. Slide lock nut and ferrule onto each tube. (See Fig. 6.)
FIELD POWER
SUPPLY CONN
FERRULE
LOCK NUT
7
⁄ ″ DIA HOLE WITH
8
1
1 ⁄ ″ DIA KNOCKOUT
8
3
AND 1 ⁄ ″ DIA
8
KNOCKOUT
FIELD CONTROL
SUPPLY CONN
7
⁄ ″ DIA HOLE
8
SUCTION LINE CONN
LIQUID LINE CONN
TUBING
A97009
A92121
LIQUID TUBE
VAPOR TUBE
Fig. 6—Lock Nut/Ferrule Positioning (38CKQ)
UNIT SIZE
Conn Dia
Tube Dia
3/8
Conn Dia
5/8
Tube Dia
5/8
4. Apply a few drops of refrigerant oil to ferrule and valve
threads to reduce assembly torque and assist sealing.
018, 024
030, 036
042, 048
060
3/8
3/8
3/8
3/8
3/8
3/4
3/4
3/8
7/8
7/8
5. Insert tube end into service valve until it bottoms.
3/8
7/8
1-1/8
6. Push ferrule into place and hand tighten nut until an increase
in torque is felt.
NOTE: Tube diameters are for lengths up to 50 ft. For tubing lengths greater
than 50 ft, consult your local distributor.
7. Mark nut and tube and tighten 1-1/2 turns from mark. (See
Fig. 7.) Keep tube bottomed in valve while tightening nut.
If refrigerant tubing or indoor coil is exposed to atmosphere, it
must be evacuated to a minimum of 500 microns to eliminate
contamination and moisture in the system.
NOTE: A backup wrench on the hex part of the suction valve is
required while tightening.
Fig. 4—Refrigerant Tube Dimensions/Connections
4. 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.
The tube end must stay bottomed in the service valve during
final assembly to ensure proper seating, sealing, and rigidity.
MECHANICAL FITTING REPAIR
5. Refrigerant tubing and indoor coil are now read for leak
testing. This check should include all field and factory joints.
To replace damaged ferrule or tubing proceed as follows.
1. Attach gages to service valves.
MECHANICAL CONNECTION (38CKQ MODELS)
2. Close liquid service valve and operate unit to pump refrigerant
charge into condenser coil.
1. Cut tubing to correct length, deburr, and size as necessary,
making sure tube ends are square. If a large burr is evident, ID
and OD must be deburred to allow tube to bottom in valve.
3. When suction pressure reaches 5 psig, shut unit off. Do not
operate unit in a vacuum.
2. Remove lock nuts and ferrules from plastic bags taped to
service panel. (See Fig. 5.)
4. Close suction service valve and recover refrigerant in tubing.
5. Back-off locknut and ferrule onto tube.
6. Remove damaged part of tubing using tubing cutter. Repeat
installation procedure previously outlined using new ferrule.
7. Evacuate tubing set and indoor coil. Check for leaks.
VALVE FITTING
FERRULE
8. Open service valves or recharge unit. Check refrigerant
charge.
Step 7—Install Solenoid Valve In Liquid Tube (If Re-
quired)
Not all applications require use of a liquid tube solenoid
valve. If your unit has been shipped with a liquid tube
solenoid valve in the unit, it must be installed for performance
enhancement. The liquid tube solenoid valve must be ener-
gized during evacuation for complete removal of refrigerant.
LOCK NUT
Before making liquid tube connections, install factory-supplied
solenoid valve on indoor liquid fitting. (See Fig. 8.) Be sure to use
flare adapter supplied with the indoor coil when making connec-
tions.
A92120
Fig. 5—Mechanical Fitting Assembly (38CKQ)
3
5. Wire solenoid coil into system control circuit.
LOCK NUT
Step 8—Make Electrical Connections
To avoid personal injury or death, do not supply power to unit
with compressor terminal box cover removed.
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.
TUBING
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 or phase imbalance (3 phase)
may fluctuate above or below permissible limits.
MARK ON LOCK NUT
AND TUBE
A92122
Fig. 7—Proper Marking of Valve Assembly (38CKQ)
NOTE: Use copper wire only between disconnect switch and
unit.
ELECTRICAL JUNCTION
ELECTRICAL COIL
NOTE: Install branch circuit disconnect of adequate size per
NEC to handle unit starting current. Locate disconnect within sight
from and readily accessible from unit, per Section 440-14 of NEC.
ROUTE GROUND AND POWER WIRES — Remove access
panel to gain access to unit wiring. Extend wires from disconnect
through power wiring hole provided and into unit control box.
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.
VALVE
FLOW ARROW
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. 9.
3
STRAIGHT
/
IN. STUD
8
NOTE:System flow direction
must match arrow on
bottom of body.
DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES
A87044
CONTACTOR
Fig. 8—Solenoid Valve Installation
FIELD POWER
WIRING
Wiring must comply with local codes and NEC requirements,
if a field-supplied control power source is needed when
adding solenoid.
BLUE
3 PHASE ONLY
1. Remove coil liquid connection cap and discard.
FIELD GROUND
WIRING
2. Mount solenoid valve on liquid tube, making sure valve flow
arrow points toward indoor coil. Mount valve in any position
except valve body at top and electric coil at bottom. (See Fig.
8.) Solenoid valve is to be installed a maximum of 2 ft from
indoor coil.
GROUND
LUG
A94025
Fig. 9—Line Power Connections
CONNECT CONTROL WIRING — Route 24-v control wires
through control wiring grommet and connect leads to control
wiring. (See Fig. 10.)
Avoid valve damage while brazing by wrapping valve with a
heat-sinking material such as a wet cloth.
Use No. 18 AWG color-coded, insulated (35°C minimum) wire. If
thermostat is located more than 100 ft from unit, as measured
along the control voltage wires, use No. 16 AWG color-coded wire
to avoid excessive voltage drop.
3. Braze valve onto end of liquid tube using silver bearing or
non-silver bearing brazing material. Consult local code re-
quirements.
Use furnace transformer, fan coil transformer, or accessory trans-
former for control power, 24-v/40-va minimum.
4. Braze flare adapter onto outlet end of solenoid valve.
4
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.
Do not vent refrigerant to atmosphere. Recover during system
repair or final unit disposal.
Step 9—Compressor Crankcase Heater
Follow these steps to properly pumpdown a system and avoid
negative suction pressure.
When equipped with a crankcase heater, furnish power to heater a
minimum of 24 hr before starting unit. To furnish power to heater
only, set thermostat to OFF and close electrical disconnect to
outdoor unit.
1. Fully back seat (open) liquid and vapor tube service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Replace stem caps after system is opened to
refrigerant flow. Replace caps finger-tight and tighten with
wrench an additional 1/6-turn for front seating valves (female
hex stem) or 1/12 turn for back seating valves (male square
stem).
A crankcase heater is required if refrigerant tubing is longer than
50 ft.
NOTE: The Seasonal Energy Efficiency Ratio (SEER) is ob-
tained with crankcase heater de-energized. To de-energize crank-
case heater, disconnect black crankcase heater wires at contactor.
After disconnecting, make sure wires are isolated from all other
electrical connections and components to prevent electrical short-
ing.
3. Close electrical disconnects to energize system.
4. Set room thermostat at desired temperature. Be sure set point
is below indoor ambient temperature.
5. Set room thermostat to COOL and fan to FAN or AUTO
mode, as desired. Operate unit for 15 minutes. Check system
refrigerant charge.
Step 10—Install Electrical Accessories
Refer to the individual instructions packaged with kits or acces-
sories when installing.
6. Factory charge is shown on unit rating plate. Adjust charge by
following procedure shown on charging tables located on unit.
Step 11—Start-Up and Check Charge
SEQUENCE OF OPERATION
Turn on power to indoor and outdoor units. Transformer is
energized.
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
On a call for cooling, thermostat makes circuits R-Y and R-G.
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.
In scroll compressor applications:
• Dome temperatures may be hot.
When thermostat is satisfied, its contacts open, de-energizing
contactor and blower relay. Compressor and motors stop.
• In 3 phase application, incorrect phasing will cause reverse
rotation, resulting in elevated noise levels, equalized pres-
sures, and reduced current draw. Correct by reversing power
connection L1 and L2 on contactor.
If indoor unit is equipped with a time-delay relay circuit, the
indoor blower will run an additional 90 sec to increase system
efficiency.
CARE AND MAINTENANCE
To prevent personal injury wear safety glasses, protective
clothing, and gloves when handling refrigerant and observe
the following:
• Back seating service valves are not equipped with Schrader
valves. Fully back seat (counter clockwise) valve stem before
removing gage port cap.
For continued high performance and to minimize possible equip-
ment failure, periodic maintenance must be performed on this
equipment.
Leave User’s Manual with homeowner. Explain system operation
and periodic maintenance requirements outlined in manual. Fre-
quency of maintenance may vary depending on geographic areas,
such as coastal applications which require more frequent mainte-
nance.
• Front seating service valves are equipped with Schrader
valves.
5
CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
FA, FB, FC,
FD, FF
FAN COIL
AIR
CONDITIONER
MODEL AC
SINGLE
STAGE
AIR
R
R
24 VAC HOT
MODEL AC
CONDITIONER
FURNACE
R
C
R
24 VAC HOT
24 VAC COM
C
W/W1
Y/Y2
G
24 VAC COM
C
SEE
C
C
NOTE 2
HEAT STAGE 1
COOL STAGE 1
INDOOR FAN
W2
SEE
W/W1
C
NOTE 2
HEAT STAGE 1 W/W1
Y/Y2
G
Y/Y2
G
COOL STAGE 1
INDOOR FAN
G
A94385
A94384
CORPORATE
PROGRAMMABLE
THERMOSTAT
MODEL AC
CORPORATE
PROGRAMMABLE
THERMOSTAT
MODEL AC
FA, FB, FC,
FD, FF
AIR
SINGLE
CONDITIONER
FAN COIL
AIR
STAGE
CONDITIONER
FURNACE
R
R
G
24 VAC HOT
INDOOR FAN
HEAT STAGE 1
COOL STAGE 1
NOT USED
R
R
G
24 VAC HOT
INDOOR FAN
HEAT STAGE 1
COOL STAGE 1
NOT USED
G
W/W1
Y/Y2
G
W2
W/W1
Y/Y2
W/W1
Y/Y2
SEE
NOTE 2
O/W2
O/W2
C
SEE
NOTE 2
Y1/W2
NOT USED
C
Y1/W2
NOT USED
24 VAC COM
NOT USED
NOT USED
C
B
L
C
24 VAC COM
NOT USED
NOT USED
C
C
B
L
OPTIONAL
OUTDOOR
SENSOR
S1
S2
OPTIONAL
OUTDOOR
SENSOR
S1
S2
CONNECTION
CONNECTION
A94386
A94387
Fig. 10—Typical 24-v Circuit Connections
6
CORPORATE
PROGRAMMABLE
THERMOSTAT
MODEL AC
CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
FK4B
FAN COIL
AIR
CONDITIONER
FK4B
AIR
MODEL AC
FAN COIL
CONDITIONER
R
R
G
24 VAC HOT
INDOOR FAN
HEAT STAGE 1
COOL STAGE 1
NOT USED
R
C
R
C
24 VAC HOT
24 VAC COM
G
W/W1
Y/Y2
W2
Y/Y2
O
SEE
C
NOTE 2
HEAT STAGE 1 W/W1
COOL STAGE 1 Y/Y2
W2
Y/Y2
SEE
NOTE 2
O/W2
C
INDOOR FAN
G
G
Y1/W2
NOT USED
Y1
W3
C
W3
24 VAC COM
NOT USED
NOT USED
O
Y1
E
C
B
L
E
L
OPTIONAL
OUTDOOR
SENSOR
S1
S2
L
A94388
CONNECTION
A94389
NON-CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
FK4B
FAN COIL
AIR
MODEL AC
CONDITIONER
R
R
24 VAC HOT
C
SEE
C
NOTE 2
HEAT STAGE 1
COOL STAGE 1
INDOOR FAN
W
Y
W2
Y/Y2
G
G
W3
O
Y1
E
L
A95281
Fig. 10—Typical 24-v Circuit Connections (Continued)
7
NON-CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
NON-CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
FA, FB, FC,
FD, FF
FAN COIL
AIR
CONDITIONER
MODEL AC
SINGLE
STAGE
AIR
MODEL AC
CONDITIONER
FURNACE
R
R
24 VAC HOT
R
R
24 VAC HOT
C
C
SEE
C
NOTE 2
W
Y
HEAT STAGE 1
COOL STAGE 1
INDOOR FAN
W2
SEE
W/W1
C
NOTE 2
HEAT STAGE 1
COOL STAGE 1
INDOOR FAN
W
Y
Y/Y2
G
G
G
G
A95282
A95283
NOTES:
1. CORPORATE THERMOSTAT WIRING DIAGRAMS ARE ONLY ACCURATE FOR MODEL
NUMBERS BEGINNING WITH TSTAT _ _ _ _ _ _ _
2. WIRING MUST CONFORM TO NEC OR LOCAL CODE.
3. SOME UNITS ARE EQUIPPED WITH PRESSURE SWITCH(ES), TEMPERATURE SWITCH,
OR 5 MINUTE COMPRESSOR CYCLE PROTECTION. CONNECT 24 VOLT FIELD WIRING
TO FACTORY PROVIDED STRIPPED LEADS.
4. A LIQUID LINE SOLENOID VALVE IS REQUIRED ON SOME UNITS. SEE SPECIFIC UNIT
INSTRUCTIONS.
5. THERMOSTATS ARE FACTORY CONFIGURED WITH 5 MINUTE COMPRESSOR CYCLE
PROTECTION AND 4 CYCLES PER HOUR LIMIT. SEE THERMOSTAT INSTRUCTIONS
FOR DETAILS.
6. TO STAGE THE ELECTRIC RESISTANCE HEAT, CONSULT OUTDOOR THERMOSTAT
INSTALLATION INSTRUCTIONS.
LEGEND
24 VOLT FACTORY WIRING
24 VOLT FIELD WIRING
FIELD SPLICE CONNECTION
C
CONTACTOR
A94394
Fig 10—Typical 24-v Circuit Connections (Continued)
Copyright 1997 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
38brc1si
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 3a 2a
1
4
PC 101
Catalog No. 533-840
Printed in U.S.A.
Form 38BRC-1SI
Pg 8
2-97
Replaces: New
|