LG LWC0961AHG Service Manual ▷ View online
—26—
COMPLAINT
CAUSE
REMEDY
If restricted, clean or replace.
Close if open.
Determine if the unit is properly sized for the
area to be cooled.
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.
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.
tubing not to contact cabinet, compressor, shroud,
and barrier.
Check the voltage at outlet. If none, correct.
Check the terminals. If loose, repair or replace.
Check for continuity, refer to the wiring diagram for
terminal identification. Replace the switch if the
circuit is open.
terminal identification. Replace the switch if the
circuit is open.
Check setting. Turn to warmest position.
Check the position of knob. If not at the warmest
setting, advance knob to this setting. Check conti-
nuity of the thermostat. Check continuity of control
by removing lead from terminal, turn the
selector switch to heat, and check between com-
mon terminal and H terminal. (NOTE: Room tem-
perature should be 30°C(86°F) or lower when test-
ing the temperature control.) If no continuity
exists, replace thermostat.
setting, advance knob to this setting. Check conti-
nuity of the thermostat. Check continuity of control
by removing lead from terminal, turn the
selector switch to heat, and check between com-
mon terminal and H terminal. (NOTE: Room tem-
perature should be 30°C(86°F) or lower when test-
ing the temperature control.) If no continuity
exists, replace thermostat.
Selector switch must be in the " " mode.
Check continuity of the switch. Continuity should
be between terminals identified on wiring diagram
when the switch is in heat mode.
be between terminals identified on wiring diagram
when the switch is in heat mode.
Check continuity of the reverse valve coil.
Continuity should be between two lead wires.
If none, check the reverse valve body.
Replace the part which is defective.
Continuity should be between two lead wires.
If none, check the reverse valve body.
Replace the part which is defective.
Air filter
Exhaust damper door
Unit undersized
Blower or fan
Copper tubing
No power
Wiring
Rotary switch
Temperature control position
Thermostat
(Temperature control)
(Temperature control)
Selector switch position
Selector switch
Reverse valve
Insufficient cooling or
heating.
heating.
Excessive noise.
No heat.
—18—
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.
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 outdoor coil
(heat exchanger) & the fan
operation.
(heat exchanger) & the fan
operation.
Check gas leakage.
Repair gas leak.
Replacement of unit if the
unit is beyond repair.
unit is beyond repair.
Satisfactory operation with
temperature difference of
inlet & outlet air ;
44~50
temperature difference of
inlet & outlet air ;
44~50
°
F(7~10
°
C)
Check heat load
increase.
increase.
Clean condenser.
Not on separate circuit.
Check inside gas
pressure.
pressure.
Adjusting of refrigerant
charged.
charged.
Malfunction of compressor.
Replacement of
compressor.
compressor.
Check cold air circulation
for smooth flow.
for smooth flow.
Dirty indoor coil
(Heat exchanger)
(Heat exchanger)
Stop of auto air-swing
Correct above trouble
Check clogging in refrigera-
tion circuit.
tion circuit.
Repair clogging in refrigera-
tion circuit.
tion circuit.
Obstruction at air outlet
Clogged of air filter.
Malfunction of fan
—19—
Fails to Start
Check circuit breaker
and fuse.
and fuse.
Gas leakage of feeler bulb
of thermostat
of thermostat
Check of control switch.
Fan only fails to start.
Improper wiring.
Defect of fan motor
capacitor.
capacitor.
Irregular motor resistance
( ).
Irregular motor insulation
( ).
( ).
Irregular motor insulation
( ).
Replacement of fan motor.
Regular but fails to start.
Replacement of compressor
(locking of rotor, metal).
(locking of rotor, metal).
Improper thermostat setting.
Loose terminal connection.
Improper wiring.
Irregular motor resistance ( )
Irregular motor insulation ( )
Replacement of compressor
(Motor damaged)
(Motor damaged)
Drop of power voltage.
Capacitor check.
Replacement
Compressor only fails to
start.
start.
Defect of compressor
capacitor.
capacitor.
Check of power source.
Check of control switch
setting.
setting.
—20—
• Check the Fuse.
• Check the wiring diagram.
• Check the wiring diagram.
Is the Trans input power
the same as specified?
Is the Trans output power
about AC 14V?
Is shorted the Trans. output?
Is output Voltage of IC01D
DC 12V?
Is output Voltage of IC02D
DC 5V?
Is the voltage No.18 of Micom
DC 5V?
Exchange Main PCB Ass'y.
Is the
connection between
Main and Display
all right?
Is the reset circuit all right?
(The No.14 of
Micom is 5V.)
• Check the Fuse.
• Check the wiring diagram.
• Check the wiring diagram.
• Check the Main
PCB pattern.
PCB pattern.
• Exchange the Trans.
• Exchange D02D~D05D.
• Exchange IC01D.
• Exchange IC01D.
• Exchange IC02D.
• Exchange IC01A, C02A.
• Connect connector
exactly.
exactly.
• Check the PCB
pattern.
pattern.
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
NO
YES
■
ELECTRICAL PARTS TROUBLESHOOTING GUIDE
Possible Trouble 1
The unit does not operate.
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