LG LP-F8081ZL Service Manual ▷ View online
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8.3 The unit is working, but not cooling and heating sufficiently
(Both blower and compressor are working)
WHAT TROUBLED
COMPLAINTS
HOW TO CHECK
REMEDY
Load
Air flow
Short air volume
Refrigerant
Air passage
Air filter
Much heat load
Obstacle disturbs Intake
of uniform wind.
of uniform wind.
Reverse rotation of
blower.
blower.
Shortage in the charged
refrigerant.
refrigerant.
Improper or foreign bodies
Clogged with dust
Heat load increased.
Window or door has
many cracks or gaps.
Window or door has
many cracks or gaps.
Checking
Checking
Coil inlet pipe is frosted
Checking
Checking
Do necessary disposal
respectively.
respectively.
Correct it.
Correct it.
Replenish it.
(Repair the leakage spot).
(Repair the leakage spot).
Correct or clear the
foreign bodies.
foreign bodies.
Cleaning
8.4 All the functions are performed normally, but very noisily and
much vibratively.
WHAT TROUBLED
COMPLAINTS
HOW TO CHECK
REMEDY
Compressor
Blower
Screws
• Checking
• Checking
Checking
Checking
• Remove the shipping
bracket.
• Replace the
compressor
• Repair or replace it.
• Clear the other
• Clear the other
material
Repair
Liquid refrigerant flooding
back from the evaporator.
back from the evaporator.
Compressor shipping
bracket is not removed.
bracket is not removed.
Faulty discharge valve
and suction valve.
and suction valve.
Fan broken.
Other materials intruded.
Looseness or fail-off of
screws
screws
• Check for refrigerant over-charge.
• Check to see if the intaking air temperature is
• Check to see if the intaking air temperature is
extremely cold.
• Check for insufficient air flow quantity.
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WHAT TROUBLED
COMPLAINTS
HOW TO CHECK
REMEDY
Electric troubles
(Magnetic
contactor)
(Magnetic
contactor)
Others
Defective contact.
Defective contact point.
Rusting and faults in the iron
core contact face. Defective
contact of the
operating switch.
Defective contact point.
Rusting and faults in the iron
core contact face. Defective
contact of the
operating switch.
Improper installation
Checking
Checking
Repair and clean or
replace it.
replace it.
Correct it.
Fault
Cause
Check/Correcitve Action
High Discharge
Low
Discharge
Discharge
High
Suction
Pressure
Suction
Pressure
Low
Suction
Pressure
Suction
Pressure
Condenser cooling air extremely hot or
insufficient air flow through the condenser
insufficient air flow through the condenser
Inside of the condenser tube is clogged.
Air in the refrigeration cooling cycle.
Suction pressure is higher than standard.
Faulty discharge valves or suction valves of
the compressor.
the compressor.
Refrigerant low-charge or leakage.
Suction pressure is lower than standard.
Intake air extemely hot or excessive air flow
through the evaporator coil.
through the evaporator coil.
Refrigerant over-charge.
Faulty discharge valve or suction valve of
the compressor.
the compressor.
Discharge pressure is higher than standard
Intake air extremely cold or insufficient air
flow through the evaporator coil.
flow through the evaporator coil.
Refrigerant short-charge or leakage.
Restricted liquid in the suction line.
1. Check the operation of the outdoor motor.
2. Check discharge and suction, air
2. Check discharge and suction, air
circulation.
Clean condenser coil.
Purge air from the cycle.
See "High Suction Pressure".
1. Check unit operation input
2. Check the suction pressure.
Add refrigerant: repair leakage if any.
See "Low Suction Pressure".
1. Check fresh air, intake or check for
leakage of the return air.
2. Check air flow quantity.
Purge the refrigerant.
Check the operating input.
See "High discharge Pressure".
1. Check air flow quantity.
2. Check air filter.
3. Check evaporator coil frosting
Add refrigerant, repair leakage, if any.
Check the capillary tube and the strainer.
8.5 Trouble checking by protection devices
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Fault
Cause
Check/Correcitve Action
Overcurrent
Relay for
Compressor
Cut-Off
Relay for
Compressor
Cut-Off
Overcurrent
Relay for
Fan Motor
Cut-Off
Relay for
Fan Motor
Cut-Off
Fuse Blown
Disconnection
and Faulty
Contact
and Faulty
Contact
Discharge pressure is lower than standard.
Single or three phases running.
High or low voltage or phase unbalance.
Refrigerant short charge or leakage.
Compressor frequently stops and starts.
Discharge and suction pressure are
extremely high.
extremely high.
High or low voltage, or phase unbalance.
Single or three phases running
Faulty compressor motor.
Loose connections.
Compressor frequently stops and starts.
High or low voltage, or phase unbalance.
Single or three phases running.
Faulty fan motor.
Loose connection.
Faulty fan bearing.
Loose connections.
Single or three phase running.
Faulty motor.
Disconnection.
Faulty contact.
See "Low Discharge Pressure".
Check the power supply line and the
contactor.
contactor.
Check the voltage and phase unbalance.
Add refrigerant, repair leakage, if any.
Check thermistor operation, or any other
cause for frequent stop and start operation.
cause for frequent stop and start operation.
See "High Discharge Pressure" or "High
Suction Pressure".
Suction Pressure".
Check the voltage and phase unbalance.
Check the power supply line and the
contact.
contact.
Check electric resistance among the
compressor terminals, and from the
terminals to ground.
compressor terminals, and from the
terminals to ground.
Check the electric connections.
Check the operation of the thermistor, or
any other cause for frequent stop.
any other cause for frequent stop.
Check the voltage and electric wiring.
Check the power supply line and the
contactor.
contactor.
Check the fan motor and wiring.
Check the elelctric connections.
Check repair or replace the bearing.
Check the electric connections.
Check the power supply line.
Check electric resistance among motor
housing, and from the terminals to
ground.
housing, and from the terminals to
ground.
1. Check the wires and connect where
necessary.
2. Check the contact holding coil.
Check the contact in the magnetic
contact, the over-current relay, the
pressure control switch, the operation
switch, the auxiliary relay.
contact, the over-current relay, the
pressure control switch, the operation
switch, the auxiliary relay.
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8.6 Electronic Parts Troubleshooting Guide
1) No cooling operation performed.
YES
YES
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
Is the AC220V
(AC 240 V) between Connector(CN-
outunit)
¥L
and
¥N
of Main
P.C.B
ON/OFF S/W ON
Is the unit operating?
Is the input power
AC220V (AC240V) at COMP
Magnetic coil?
Check the magnetic
contactor of outdoor unit.
contactor of outdoor unit.
Is it Cooling mode?
Room temp, > Set temp?
Is the DC5V at 14
pin of IC1(MICOM)
Replacement ICO2M, RY-Comp
Replacement (MICOM)
Room temp, >set temp
setting
setting
Select the cooling
operation mode.
operation mode.
Check the wiring
diagram.
diagram.
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