LG BWC076GBAA0 User manual

Room Air Conditioner
SERVICE MANUAL
CAUTION
-BEFORE SERVICING THE UNIT, READ THE SAFETY
PRECAUTIONS IN THIS MANUAL.
-ONLY FOR AUTHORIZED SERVICE PERSONNEL.
MODEL: BWC076GBAA0
BWC096GBAA0
BWC126CBAA0
(Applied to new refrigerant R-410A)
website http://biz.LGservice.com
e-mail http://www.LGEservice.com/techsup.html

—2—
1. PREFACE
1.1 SAFETY PRECAUTIONS................................2
1.2 INSULATION RESISTANCE TEST .................2
1.3 SPECIFICATIONS...........................................3
1.4 FEATURES......................................................4
1.5 CONTROL LOCATIONS .................................4
2. DISASSEMBLY INSTRUCTIONS
2.1 MECHANICAL PARTS ....................................5
2.1.1 FRONT GRILLE .....................................5
2.1.2 CABINET ................................................5
2.1.3 CONTROL BOX .....................................5
2.2 AIR HANDLING PARTS ..................................6
2.2.1 AIR GUIDE AND BLOWER ....................6
2.2.2 FAN ........................................................6
2.2.3 SHROUD ................................................6
2.3 ELECTRICAL PARTS......................................7
2.3.1 COMPRESSOR......................................7
2.3.2 CAPACITOR...........................................7
2.3.3 POWER CORD ......................................8
2.3.4 THERMOSTAT.......................................8
2.3.5 ROTARY SWITCH .................................8
2.3.6 MOTOR ..................................................8
2.4 REFRIGERATING CYCLE ..............................9
2.4.1 CONDENSER.........................................9
2.4.2 EVAPORATOR.......................................9
2.4.3 CAPILLARY TUBE .................................9
3. INSTALLATION
3.1 SELECT THE BEST LOCATION...................12
3.2 CHECK OF INSTALLATION..........................12
3.3 HOW TO DRAIN............................................12
3.4 HOW TO INSTALL ........................................13
3.5 HOW TO USE THE REVERSIBLE
INLET GRILLE...............................................14
4. TROUBLESHOOTING GUIDE
4.1 OUTSIDE DIMENSIONS ...............................15
4.2 PIPING SYSTEM...........................................15
4.3 TROUBLESHOOTING GUIDE ......................16
5. SCHEMATIC DIAGRAM
5.1 CIRCUIT DIAGRAM ......................................20
6. EXPLODED VIEW AND
REPLACEMENT PARTS LIST........22
1. PREFACE
This SERVICE MANUAL provides various service information, including the mechanical and electrical
parts etc. This room air conditioner was manufactured and assembled under a strict quality control system.
The refrigerant is charged at the factory. Be sure to read the safety precautions prior to servicing the unit.
1.1 SAFETY PRECAUTIONS
1. When servicing the unit, set the ROTARY SWITCH
or POWER SWITCH to OFF and unplug the power
cord.
2. Observe the original lead dress.
If a short circuit is found, replace all parts which
have been overheated or damaged by the short
circuit.
3. After servicing the unit, make an insulation resis-
tance test to protect the customer from being
exposed to shock hazards.
1.2 INSULATION RESISTANCE TEST
1. Unplug the power cord and connect a jumper
between 2 pins (black and white).
2. The grounding conductor (green) is to be open.
3. Measure the resistance value with an ohm meter
between the jumpered lead and each exposed
metallic part on the equipment at all the positions
(except OFF) of the ROTARY SWITCH.
4. The value should be over 1MΩ.
CONTENTS

—3—
POWER SUPPLY
COOLING CAPACITY (Btu/h)
INPUT (W)
RUNNING CURRENT (A)
E.E.R (Btu/h.W)
INDOOR (°C)
OUTDOOR (°C)
REFRIGERANT (R-410A) CHARGE
EVAPORATOR
CONDENSER
FAN, INDOOR
FAN, OUTDOOR
FAN SPEED STEPS, FAN/COOLING
FAN MOTOR
OPERATION CONTROL
ROOM TEMP. CONTROL
AIR DIRECTION CONTROL
CONSTRUCTION
PROTECTOR COMPRESSOR
FAN MOTOR
POWER CORD
DRAIN SYSTEM
NET WEIGHT (lbs/kg)
OUTSIDE DIMENSION (inch)
(W H D) (mm)
7,000 9,000 12,000
775 1,000 1,340
3.4 4.5 6.0
9.0 9.0 9.0
27(DB) * 19(WB)**
35(DB) * 24(WB)**
350g 500g 450g
2 ROW 14 STACKS 3 ROW 14 STACKS 2 ROW 13 STACKS
2 ROW 16 STACKS 2 ROW 16 STACKS 2 ROW 18 STACKS
TURBO FAN
PROPELLER TYPE FAN WITH SLINGER-RING
2/3
4 POLES
ROTARY SWITCH
THERMOSTAT
VERTICAL LOUVER (RIGHT & LEFT)
HORIZONTAL LOUVER (UP & DOWN)
SLIDE IN-OUT CHASSIS
INTERNAL OVERLOAD PROTECTOR
INTERNAL THERMAL PROTECTOR
1.8m (3 WIRE WITH GROUDING)
ATTACHMENT PLUG (CORD-CONNECTED TYPE)
DRAIN PIPE OR SPLASHED BY FAN SLINGER
66/30 66/30 88/40
18.46 x 13.90 x 20.67 18.46 x 13.90 x 20.67 23.62x 14.96x 21.85
469 x 353 x 525 469 x 353 x 525 600 x 380 x 555
1ø, 220-240V~, 50Hz
BWC076GBAA0 BWC096GBAA0 BWC126CBAA0
MODELS
ITEMS
OPERATING
CONDITION
1.3 SPECIFICATIONS
* DB:Dry Bulb
** WB:Wet Bulb

1.4 FEATURES
• Designed for COOLING ONLY.
• Powerful and whisper cooling.
• Slide-in and slide-out chassis for the simple
installation and service.
• Side air-intake, side cooled-air discharge.
1.5 CONTROL LOCATIONS
• VENTILATION
The ventilation lever must be in the CLOSE position
in order to maintain the best cooling conditions.
When fresh air is necessary in the room, set the
ventilation lever OPEN position. The damper is
opened and room air is exhausted.
• THERMOSTAT
Thermostat will automatically control the
temperature of the room.
Select the right side for lower room temperature.
The temperature is selected by turning the knob to
the desired position. The middle position of arc is a
normal setting for average conditions.
• OPERATION
OFF ( ) : Turns the air conditioner
off.
MED FAN ( ) : Permits the medium fan
speed operation without
cooling.
LOW FAN ( ) : Permits the low fan
speed operation without
cooling.
HIGH COOL ( ) : Permits cooling with the
high fan speed operation.
MED COOL ( ) : Permits cooling with the
medium fan speed
operation.
LOW COOL ( ) : Permits cooling with the
low fan speed operation.
• Built-in adjustable THERMOSTAT
• Washable one-touch filter
• Compact size
• Reliable and efficient rotary compressor is equipped.
—4—
CLOSE VENT OPEN
0
0

—5—
2.1 MECHANICAL PARTS
2.1.1 FRONT GRILLE
1. Open the lnlet grille upward or downward.
(See Figure 1)
2. Remove the screw which fastens the front grille.
3. Pull the front grille from the right side.
4. Remove the front grille.
5. Re-install the component by referring to the
removal procedure, above.
2.1.2 CABINET
1. After disassembling the FRONT GRILLE, remove
the 2 screws which fasten the cabinet at both
sides.
2. Remove the 2 screws which fasten the cabinet at
back.
3. Pull the base pan forward. (See Figure 2)
4. Remove the cabinet.
5. Re-install the component by referring to the
removal procedure, above.
2.1.3 CONTROL BOX
1. Remove the front grille. (Refer to section 2.1.1)
2. Remove the cabinet. (Refer to section 2.1.2)
3. Remove the 2 screws which fasten the control box
cover.
4. Remove two housings which connect compressor
wire and motor wire in the control box.
5.Discharge the capacitor by placing a 20,000
ohmresistor across the capacitor terminals.
6. Remove the 2 screws which fasten the control
box.
7. Pull the control box forward completely.
8. Re-install the components by referring to the
removal procedure, above. (See Figure 3)
(Refer to the circuit diagram found on page 20 in
this manual and on the control box.)
2. DISASSEMBLY INSTRUCTIONS
—Before the following disassembly, POWER SWITCH set to OFF and disconnect the power cord.
Figure 1
Figure 3
1
ThermostatOperation
2
3
4
9
8
7
6
5
Off
Med
Fan
Low
Fan
High
Cool
Med
Cool
LowCool
1
Thermostat Operation
2
3
4
9
8
7
6
5
Off
Med
Fan
Low
Fan
High
Cool
Med
Cool
LowCool
Figure 2

—6—
2.2 AIR HANDLING PARTS
2.2.1 AIR GUIDE AND BLOWER
1. Remove the front grille. (Refer to section 2.1.1)
2. Remove the cabinet. (Refer to section 2.1.2)
3. Remove the control box. (Refer to section 2.1.3)
4. Remove the 4 screws which fasten the brace.
5. Remove the brace.
6. Remove the 2 screws which fasten the evaporator.
7. Move the evaporator high side forward and pulling
it upside slightly. (See Figure 4)
8. Move the evaporator sideways carefully.
9. Pull out upside hook of orifice by pushing the tabs
and remove it. (See Figure 5)
10. Remove the clamp with hand plier which secures
the blower.
11. Remove the blower.
12. Remove the 4 screws which fasten the air guide
from the barrier.
13. Move the air guide backward and pulling out from
the base pan
14. Re-install the components by referring to the
removal procedure, above.
2.2.2 FAN
1. Remove the cabinet. (Refer to section 2.1.2)
2. Remove the brace (Refer to section 2.2.1)
3. Remove the 4 screws which fasten the condenser.
4. Move the condenser sideways carefully.
5. Remove the clamp which secures the fan.
6. Remove the fan. (See Figure 6)
7. Re-install by referring to the removal procedure.
1
ThermostatOperation
2
3
4
9
8
7
6
5
Off
Med
Fan
Low
Fan
High
Cool
Med
Cool
LowCool
Figure 4
Figure 5
Figure 6

—7—
2.2.3 SHROUD
1. Remove the fan. (Refer to section 2.2.2)
2. Remove the screw which fastens the shroud.
3. Remove the shroud. (See Figure 7)
4. Re-install the component by referring to the
removal procedure, above.
2.3 ELECTRICAL PARTS
2.3.1 COMPRESSOR
1. Remove the cabinet. (Refer to section 2.1.2)
2. Discharge the refrigerant system using a FreonTM
Recovery System.
If there is no valve to attach the recovery system,
install one (such as a WATCO A-1) before venting
the FreonTM. Leave the valve in place after
servicing the system.
3. After purging the unit completely, unbraze the
suction and discharge tubes at the compressor
connections.
4. Remove the 3 nuts and the 3 washers which
fasten the compressor.(See Figure 8)
5. Remove the compressor.
6. Re-install the components by referring to the
removal procedure, above.
2.3.2 CAPACITOR
1. Remove the control box. (Refer to section 2.1.3)
2. Remove the knobs and the screw which fasten
control panel from control box.
3. Remove the screw which located in the front.
4. Open the bottom side of control box.
5. Remove the screw and the clamp which fastens
the capacitor.
6. Disconnect all the leads of capacitor terminals.
7. Re-install the components by referring to the
removal procedure, above. (See Figure 9)
Figure 8
Figure 9
Figure 7

—8—
2.3.3 POWER CORD
1. Remove the control box. (Refer to section 2.1.3)
2. Open the control box. (Refer to section 2.3.2)
3. Disconnect the grounding screw from the control
box.
4. Disconnect the 2 receptacles.
5. Remove a screw which fastens the clip cord.
(See Figure 10)
6. Remove the power cord.
7. Re-install the component by referring to the above
removed procedure, above.
(Use only one ground-marked hole for ground
connection.)
8. If the supply cord is damaged, it must be replaced
by a special cord or assembly available from the
manufacturer or its service agent.
2.3.4 THERMOSTAT
1. Remove the control box. (Refer to section 2.1.3)
2. Open the control box. (Refer to section 2.3.2)
3. Remove the 2 screws which fasten the thermostat.
4. Disconnect 2 leads of thermostat terminals.
5. Remove the thermostat.
6. Re-install the components by refereing to the
above removal procedure. (See Figure 11)
2.3.5 ROTARY SWITCH
1. Remove the control box. (Refer to section 2.1.3)
2. Open the control box. (Refer to section 2.3.2)
3. Remove the 2 screws which fasten the rotary
switch.
4. Disconnect all the leads of the rotary switch
terminals.
5. Remove the rotary switch.
6. Re-install the components by referring to the
above removal procedure. (See Figure 12)
2.3.6 MOTOR
1. Remove the cabinet. (Refer to section 2.1.2)
2. Remove the evaporator. (Refer to section 2.2.1)
3. Remove the orifice. (Refer to section 2.2.1)
4. Remove the blower. (Refer to section 2.2.1)
5. Remove the fan. (Refer to section 2.2.2)
6. Remove the control box cover and disconnect 5 or
4 wires of motor housing. (Refer to section 2.1.3)
7. Remove the 4 screws which fasten the motor from
the mount motor. (See Figure 13.)
8. Remove the motor.
9. Re-install the components by referring to the
removal procedure, above.(See Figure 13.)
Figure 11
Figure 10
Figure 12
Figure 13

—9—
2.4 REFRIGERATING CYCLE
2.4.1 CONDENSER
1. Remove the cabinet. (Refer to section 2.1.2)
2. Remove the 4 screws which fasten the
brace.(Refer to section 2.2.1)
3. Remove the 5 screws which fasten the condenser
and shroud.
4. After discharging the refrigerant completely,
unbraze the interconnecting tube at the condenser
connections.
5. Remove the condenser.
6. Re-install the component by referring to notes.
(See Figure 14)
2.4.2 EVAPORATOR
1. Remove the cabinet. (Refer to section 2.1.2)
2. Remove the 2 screws which fasten the evaporator.
3. Move the evaporator sideways carefully.
(Refer to section 2.2.1)
4. After discharging the refrigerant completely,
unbraze the interconnecting tube at the evaporator
connections.
5. Remove the evaporator.
6. Re-install the component by referring to notes.
(See Figure 15)
2.4.3 CAPILLARY TUBE
1. Remove the cabinet. (Refer to section 2.1.2)
2. After discharging the refrigerant completely,
unbraze the interconnecting tube at the capillary
tube.
3. Remove the capillary tube.
4. Re-install the component by referring to notes.
Figure 14
Figure 15
•This unit is charged with R-410A, pay attention not to charge R-22.
CAUTION

—10—
—Replacement of the refrigeration cycle.
1. When replacing the refrigeration cycle, be sure to
Discharge the refrigerant system using a FreonTM
recovery System.
If there is no valve to attach the recovery system,
install one (such as a WATCO A-1) before venting the
FreonTM. Leave the valve in place after
servicing the system.
2. After discharging the unit completely, remove the
desired component, and unbraze the pinch-off tubes.
3. Solder service valves into the pinch-off tube ports,
leaving the valves open.
4. Solder the pinch-off tubes with Service valves.
5. Evacuate as follows.
1) Connect the vacuum pump, as illustrated figure
16A.
2) Start the vacuum pump, slowly open manifold
valves A and B with two full turns counterclockwise
and leave the valves open.
The vacuum pump is now pulling through valves A
and B by means of the manifold.
3) Operate the vacuum pump for 20 to 30 minutes,
until 600 microns of vaccum is obtained. Close
valves A and B, and observe vacuum gauge for
a few minutes. A rise in pressure would
indicate a possible leak or moisture remaining in
the system. With valves A and B closed, stop
the vacuum pump.
4) Remove the hose from the vacuum pump and
place it on the charging cylinder. See figure 16B.
Open valve C.
Discharge the line at the manifold connection.
5) The system is now ready for final charging.
6. Recharge as follows :
1) Refrigeration cycle systems are charged from the
High-side. If the total charge cannot be put
in the High-side, the balance will be put in the
suction line through the access valve which you
installed as the system was opened.
2) Connect the charging cylinder as shown in figure
16B.
With valve C open, discharge the hose at the
manifold connection.
3) Open valve A and allow the proper charge to
enter the system. Valve B is still closed.
4) If more charge is required, the high-side will not
take it. Close valve A.
5) With the unit running, open valve B and add the
balance of the charge.
a. Do not add the liquid refrigerant to the Low-side.
b. Watch the Low-side gauge; The pressure of
optimum condition is as below.(Cooling)
NOTE: If the actual pressure are higher than
shown, the system is most likely over-
charged, and charge should be removed.
If the actual pressure are lower than
shown, the system is most likely
undercharged, and charge should be
added.
c. Turn off valve B and allow pressure to drop.
d. Repeat steps b. and c. until the balance of the
charge is in the system.
6) When satisfied the unit is operating correctly,
use the pinch-off tool with the unit still running
and clamp on to the pinch-off tube. Using a tube
cutter, cut the pinch-off tube about 2 inches from
the pinch-off tool. Use sil-fos solder and solder
pinch-off tube closed. Turn off the unit, allow it to
set for a while, and then test the leakage of the
pinch-off connection.
NOTES
•Use vacuum pump equipped with check valve
applied to be prevented from flowing backward.
•If high vacuum equipment is used, open slowly
with the two full turns counterclockwise. This will
keep oil from foaming and being drawn into the
vacuum pump.
Do not use the existing charge set for R-22.
It is necessary to use new charge set for R-410A.
The pressure of R-410A is 1.6 times higher than
that of R-22. Thus, the high pressure side gauge of
charge set should be used higher pressure gauge
of 50kg/cm2range.
CAUTION
CAUTION
OUTSIDE TEMPERATURE THE PRESSURE OF LOW-SIDE GAUGE
35°C(95°F) 9.2~9.7 kgf/cm2.G
(130.9~138.0 lbf/in2.G)

A
COMPOUND GAUGE
EVAPORATOR
(LOW PRESSURE SIDE)
COMPRESSOR
CAPILLARY TUBE
CONDENSER
(HIGH PRESSURE SIDE)
SEE INSETS
BELOW
Fitting: UNF 1/2-20
MANIFOLD
GAUGE
B
—11—
Equipment needed: •The tools must be used according to the type of refrigerant. Never use the gauge manifold,
charge hose, charge cylinder or vacuum pump with other refrigerants. Always carry out the
work with dedicated tools.(Failure to do so could lead to trouble.)
•Vacuum pump, Charging cylinder, Manifold gauge, Brazing equipment, Pinch-off tool
capable of making a vapor-proof seal, Leak detector, Tubing cutter, Hand Tools to remove
components, Service valve.
A
CHARGING
CYLINDER
LOW HI
B
C
A
B
EXTERNAL
VACUUM PUMP
Fitting: UNF 1/2-20
Figure 16A-Pulling Vacuum Figure 16B-Charging
CAUTION
Use vacuum pump equipped with check valve
applied to be prevented from flowing backward.

—12—
3. INSTALLATION
3.1 SELECT THE BEST LOCATION
1.To prevent vibration and noise, make sure the unit
in installed securely and firmly.
2.Install the unit where the sunlight does not shine
directly on the unit.
3.There should be no obstacle, such as a
fence or wall, within 50cm from the back of the
cabinet because it will prevent heat radiation of the
condenser.
Restriction of outside air will greatly reduce the
cooling efficiency of the air conditioner.
4.Install the unit a little obliquely outward not to leak
the condensed water into the room (about 10 ~
15mm or 1/4 bubble with level).
5.Install the unit with the bottom about 70 ~ 150cm
above the floor level.
3.2 CHECK OF INSTALLATION
The setting conditions must be checked prior to
initial starting.
The undermentioned items are especially important
checking points when the installation is finished.
1. Grounding wire (Green or Green and Yellow) is
provided in the power cord. The green wire must
be grounded.
2. Connect to a single-outlet 15AMP circuit.
3. To avoid vibration or noise, make sure the air
conditioner is installed securely.
4 Avoid placing furniture or draperies in front of the
air inlet and outlet.
The air conditioner must be installed level or tilted
slightly to the outside for proper water drainage.
On exceptionally hot and humid days the air
conditioner may drain condensation through
overflow.
If the air conditioner is used in hot and a high
humidity zone, exchange the HOLE RUBBER
for the DRAIN PIPE.(See figure 18, figure 19.)
All side louvers of the cabinet must remain
exposed to the outside of the structure.
10~15mm
Over 50cm
HEAT
RADIATION
FENCE
AWNING
FOAM
COOLED
AIR
70-150cm
BASE PAN
HOLE RUBBER
DRAIN PIPE
1
BOTTOM
2
BASE PAN BOTTOM
Figure 18
Figure 19
Figure 17
CAUTION
3.3. HOW TO DRAIN (When using drain pipe)

—13—
3.4 HOW TO INSTALL
PREPARATION OF CHASSIS
1. Before installing the room air conditioner, please
install the knob. (If it is not fixed on the unit.)
2. Remove the screws which fasten the cabinet at
both sides and at the back.
3. Slide the unit from the cabinet by gripping the base
pan handle and pulling forward while
bracing the cabinet.
4. Remove the white styrofoam block from the
compressor. (Only AWC126CGAA0)
5. Slide the air conditioner into the case.
Reinstall the 2 screws removed earlier on each side
of the case.
CAUTION: The power cord must be connected to an independent
circuit. The green wire must be grounded.
6. Stuff the foam between the top of the unit and the
wall to prevent air and insects from getting into the
room.
Shipping
Screws
White
styrofoam
block
SCREWDRIVER(+, -), RULER, KNIFE, HAMMER, PENCIL, LEVEL

—14—
7. Attach the front grille to the case by inserting the
tabs on the grille into the slots on the front of the
case. Push the grille in until it snaps into place.
When you detach the front grille from the case,
push the grille to your right side and pull it toward
you.
8. Lift the inlet grill and secure the front grille with a
screw. Lower the inlet grille into place.
(In case of some models, you can secure the front grille
from the right side or lower side.)
3.5 HOW TO USE THE
REVERSIBLE INLET GRILLE
1. If you want to pull out the filter upward, open the
inlet grille slightly. Turn inside out the front grille.
Disassemble the inlet grille from the front grille
with separating the hinged part by inserting a "—"
type screw-driver tip.
Rotate the inlet grille 180 degrees and insert the
hooks into the lower holes of front grille.
Then, insert the filter.
2. Attach the front grille to the cabinet by inserting the
tabs on the grille into the tabs on the front of the
cabinet. Push the grille in until it snaps into place.
3. Lift the inlet grille and secure it with a type A screw
through the front grille.
4. If you want to pull out the filter downward, use the
reversible inlet grille without change.
(The grille is already assembled for that way.)
Inlet Grille

—15—
4. TROUBLESHOOTING GUIDE
4.1 OUTSIDE DIMENSIONS unit: mm(inch)
D W
H
4.2 PIPING SYSTEM
Following is a brief description of the important components and their function in what is called the refrigeration
system. Reference should made to figure 20 to follow the refrigeration cycle and the flow of the refrigerant in the
cooling cycle.
MOTOR
COMPRESSOR
OIL
(LIQUID REFRIGERANT)
CAPILLARY TUBE
OUTSIDE COOLING
AIR FOR REFRIGERANT
PASS THROUGH
SUCTION LINE
COOL LOW PRESSURE VAPOR
COOLED
AIR
COMPLETE LIQUID
BOIL OFF POINT
LIQUID
PRESSURE
DROP
ROOM AIR HEAT LOAD
VAPOR INLET
HOT
DISCHARGED
AIR
LIQUID OUTLET
HIGH PRESSURE VAPOR
LIQUID REFRIGERANT
LOW PRESSURE VAPOR
ROOM AIR CONITIONER
EVAPORATOR COILS CONDENSER COILS
CYCLE OF REFRIGERATION
CAPILLARY TUBE
COMPRESSOR
BLOWER
EVAPORATOR COIL
CONDENSER COIL
FAN
MOTOR
Figure 20
BWC076GBAA0
BWC096GBAA0
W x D x H
mm(inch)
469 x 353 x 525
(18.46 x 13.90 x 20.67)
600 x 380 x 555
(23.62 x 14.96 x 21.85)
BWC126CBAA0

—16—
4.3 TROUBLESHOOTING GUIDE
In general, possible trouble is classified in two kinds.
The one is called Starting Failure which is caused from an electrical defect, and the other is Ineffective Air
Conditioning caused by a defect in the refrigeration circuit and improper application.
Unit runs but poor cooling.
Ineffective Cooling
Check of outdoor coil
(heat exchanger) & the fan
operation.
Check gas leakage.
Repair gas leak.
Replacement of unit if the
unit is beyond repair.
Satisfactory operation with
temperature difference of
inlet & outlet air ;
44~50°F(7~10°C)
Check heat load
increase.
Clean condenser.
Not on separate circuit.
Check inside gas
pressure.
Adjusting of refrigerant
charge.
Malfunction of compressor.
Replacement of
compressor.
Check of cold air circulation
for smooth flow.
Dirty indoor coil
(Heat exchanger)
Correct above trouble
Check clogging in refrigera-
tion circuit.
Repair clogging in refrigera-
tion circuit.
Obstruction at air outlet
Clogged of air filter.
Malfunction of fan

—17—
Fails to Start
Check of circuit breaker.
Gas leakage of feeler bulb
of thermostat
Check of control switch.
Fan only fails to start.
Improper wiring.
Defect of fan motor
capacitor.
Irregular motor resistance
(
).
Irregular motor insulation
(
).
Replacement of fan motor.
Regular but fails to start.
Replacement of compressor
(locking of rotor, metal).
Improper thermostat setting.
Loose terminal connection.
Improper wiring.
Irregular motor resistance ( )
Irregular motor insulation ( )
Replacement of compressor
(Motor damaged)
Drop of power voltage.
Capacitor check.
Replacement
Compressor only fails to
start.
Defect of compressor
capacitor.
Check of power source.
Check of control switch
setting.

—18—
COMPLAINT CAUSE REMEDY
Check voltage at outlet. Correct if none.
Check voltage to rotary switch. If none, check
power supply cord. Replace cord if circuit is open.
Check switch continuity. Refer to wiring diagram
for terminal identification. Replace switch if defective.
Connect wire. Refer to wiring diagram for terminal
identification. Repair or replace loose terminal.
Test capacitor.
Replace if not within ±10% of manufacturer's
rating. Replace if shorted, open, or damaged.
Fan blade hitting shroud or blower wheel hitting
scroll. Realign assembly.
Units using slinger ring condenser fans must
have 1/4to 5/16 inch clearance to the base. If it is
hitting the base, shim up the bottom of the fan
motor with mounting screw(s).
Check fan motor bearings; if motor shaft will not
rotate, replace the motor.
Check voltage. See limits on this page. If not within
limits, call an electrician.
Test capacitor.
Check bearings. Does the fan blade rotate freely?
If not, replace fan motor.
Pay attention to any change from high speed to
low speed. If the speed does not change, replace
the motor.
Check grommets; if worn or missing, replace them.
If cracked, out of balance, or partially missing,
replace it.
If cracked, out of balance, or partially missing,
replace it.
Tighten it.
If knocking sounds continue when running or loose,
replace the motor. If the motor hums or noise
appears to be internal while running, replace motor.
Check voltage. See the limits on the preceeding
page. If not within limits, call an electrician.
Check the wire connections, if loose, repair or
replace the terminal. If wires are off, refer to wiring
diagram for identification, and replace. Check wire
locations. If not per wiring diagram, correct.
No power
Power supply cord
Rotary switch
Wire disconnected or
connection loose
Capacitor (Discharge
capacitor before testing.)
Will not rotate
Revolves on overload.
Grommets
Fan
Blower
Loose set screw
Worn bearings
Voltage
Wiring
Fan motor will not run.
Fan motor runs
intermittently
Fan motor noise.
Compressor will not run,
but fan motor runs.

—19—
COMPLAINT CAUSE REMEDY
Check for continuity, refer to the wiring diagram for
terminal identification. Replace the switch if circuit is
open.
Check the position of knob If not at the coldest
setting, advance the knob to this setting and restart
unit.
Check continuity of the thermostat. Replac thermostat
if circuit is open.
Check the capacitor.
Replace if not within ±10% of manufacturers rating.
Replace if shorted, open, or damaged.
Check the compressor for open circuit or ground. If
open or grounded, replace the compressor.
Check overload if the compressor temperature is
high, cool, and retest.(If not running, replace the
compressor.)
Check the voltage. See the limits on the preced-
ing page. If not within limits, call an electrician.
Check overload if the compressor temperature
is high, cool, and retest.(If not running, replace the
compressor.)
If not running, determine the cause. Replace if
required.
Remove the cabinet. inspect the interior surface of
the condenser; if restricted, clean carefully with a
vacuum cleaner (do not damage fins) or brush. Clean
the interior base before reassembling.
If condenser fins are closed over a large area on the
coil surface, head pressures will increase, causing
the compressor to cycle. Straighten the fins or
replace the coil.
Test capacitor.
Check the terminals. If loose, repair or replace.
Check the system for a restriction.
If restricted, clean of replace.
Close if open.
Determine if the unit is properly sized for the area to
be cooled.
Check the set screw or clamp. If loose or missing,
correct.
If the blower or fan is hitting air guide, rearrange the
air handling parts.
Remove the cabinet and carefully rearrange tubing
not to contact cabinet, compressor, shroud, and
barrier.
Rotary
Thermostat
Capacitor (Discharge
capacitor before
servicing.)
Compressor
Overload
Voltage
Overload
Fan motor
Condenser air flow
restriction
Condenser fins (damaged)
Capacitor
Wiring
Refrigerating system
Air filter
Exhaust damper door
Unit undersized
Blower or fan
Copper tubing
Compressor will not run,
but fan motor runs.
Compressor cycles
on overload.
Compressor cycles on
overload (Cont'd)
Insufficient cooling.
Excessive noise.

5. SCHEMATIC DIAGRAM
5.1 CIRCUIT DIAGRAM
• MODEL :BWC076GBAA0, BWC096GBAA0
—20—
POWER CORD
ROTARY SWITCH
FAN MOTOR
CAPACITOR
THERMOSTAT
COMPRESSOR ASSY
OVERLOAD PROTECTOR
1
2
3
4
5
6
7
1
1
1
1
1
1
1
S
S
S
S
S
S
S
LOCATION
NO.
DESCRIPTION
REMARKS
Q'TY
PER SET
2
1
3
4
7
6
5
COMP.
MOTOR
WH(BL)
POWER INPUT
(Plain)
GN(GN/YL)
BK(BR)
(Ribbed)
WIRING DIAGRAM 3854A20966B
BL
LB
RD
BK
R
C
S
YL
YL
RD
BK
BL
RD
ROTARY SWITCH
BK
BL
L7
1
8
6
4
2
H
M
OR(BR)
OR(BR)
BL
RD
BK
THERMOSTAT
CAPACITOR
P.T.C
RD
BK
F
C
H
BR(YL)
OLP
S: Service Parts
N: Non Service Parts