This guide explains all LG air conditioner error codes (CH series) with simple troubleshooting steps to help you identify and fix common issues safely before calling a technician.
CH 01
Indoor Unit Communication Error
- Turn OFF power for 5 minutes.
- Inspect indoor wiring connections.
- Check communication cable damage.
- Restart the unit.
CH 02
Indoor Coil Sensor Error
- Inspect indoor sensor wiring.
- Clean evaporator coil.
- Check loose connectors.
- Replace faulty sensor if needed.
CH 03
Drain Pump Error
- Check drain hose blockage.
- Inspect drain pump operation.
- Clean drain pan.
- Reset power to the unit.
CH 04
Float Switch Error
- Inspect float switch for debris.
- Check water overflow inside unit.
- Clean condensate tray.
- Replace defective float switch.
CH 05
Outdoor Communication Failure
- Inspect outdoor unit wiring.
- Check breaker and power supply.
- Verify communication cable connection.
- Restart both indoor and outdoor units.
CH 06
DC Link Voltage Error
- Check incoming voltage stability.
- Inspect inverter PCB.
- Turn OFF unit for 10 minutes.
- Contact technician if error returns.
CH 07
Mode Conflict Error
- Ensure all indoor units use same mode.
- Do not mix cooling and heating modes.
- Restart the system.
- Reset central controller if applicable.
CH 09
EEPROM Error
- Disconnect power for 10 minutes.
- Inspect PCB for damage.
- Check firmware issues.
- Replace PCB if needed.
CH 10
Fan Motor Issue
- Inspect indoor fan motor.
- Remove dust buildup.
- Check fan blade movement.
- Replace faulty motor if needed.
CH 21
DC Compressor Overload
- Turn OFF the air conditioner.
- Check for overheating.
- Inspect refrigerant levels.
- Contact HVAC technician.
CH 22
DC Compressor Problem
- Inspect compressor wiring.
- Check inverter board.
- Restart the unit.
- Professional service may be required.
CH 23
DC Link Low Voltage
- Verify stable power supply.
- Inspect electrical connections.
- Check circuit breaker.
- Restart the air conditioner.
CH 26
IPM Error
- Turn OFF power immediately.
- Inspect inverter module.
- Check for overheating signs.
- Contact LG service center.
CH 29
Compressor Phase Error
- Check electrical phase connections.
- Inspect compressor wiring.
- Verify correct voltage supply.
- Contact qualified technician.
CH 32
High Pressure Switch Error
- Clean outdoor condenser coil.
- Ensure proper ventilation.
- Check refrigerant pressure.
- Restart the unit after cooling.
CH 33
Low Pressure Switch Error
- Inspect for refrigerant leaks.
- Check air filter blockage.
- Verify proper airflow.
- Contact technician for recharge.
CH 38
Refrigerant Leak Detected
- Turn OFF the system immediately.
- Inspect for oil residue near pipes.
- Do not continue operation.
- Schedule professional leak repair.
CH 44
Outdoor Temperature Sensor Error
- Inspect outdoor sensor wiring.
- Clean outdoor unit.
- Check loose connectors.
- Replace faulty sensor.
CH 54
Phase Reversal Error
- Turn OFF power immediately.
- Check incoming power phases.
- Correct wiring sequence.
- Contact electrician if needed.
CH 67
PCB Communication Error
- Disconnect power for 10 minutes.
- Inspect PCB wiring connections.
- Check for moisture damage.
- Replace faulty PCB if necessary.
Frequently Asked Questions
What does LG AC error code CH 01 mean?
Communication error between indoor and outdoor unit.
How do I fix LG CH 03 error?
Check drain hose, pump, and restart system.
Is LG CH 38 dangerous?
Yes, it indicates refrigerant leak. Turn off immediately.
Can LG AC errors reset automatically?
Some reset after power off for 5–10 minutes.
Why does my LG air conditioner keep showing error codes?
This usually happens due to sensor failure, dirty filters, wiring issues, or unstable power supply. If the error keeps returning, professional servicing is required.
What is the most common LG AC error code?
CH 01 (communication error) and CH 05 (outdoor communication failure) are among the most common LG air conditioner error codes.
Can I use my LG AC while it shows an error code?
It is not recommended. Some errors allow limited operation, but continuing use may damage the compressor or PCB.
When should I call a technician for LG AC errors?
You should call a technician if the error involves the compressor, refrigerant leak (CH 38), PCB failure, or if the error returns after resetting.