LG Air Conditioner Error Codes

Complete LG Air Conditioner Guide

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 the 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 service if necessary.
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?
CH 01 indicates a communication problem between the indoor and outdoor units. Check wiring connections, communication cables, and restart the air conditioner.
How do I fix LG AC error code CH 03?
CH 03 usually indicates a drain pump issue. Inspect the drain hose for blockages, check pump operation, and reset the system after cleaning.
Is LG AC error code CH 38 dangerous?
Yes. CH 38 indicates a possible refrigerant leak. Turn off the air conditioner immediately and arrange professional inspection and repair.
Can LG AC error codes reset automatically?
Some temporary faults may clear after turning the unit off for 5–10 minutes. Persistent errors usually require troubleshooting or component repair.
Why does my LG air conditioner keep showing error codes?
Repeated error codes can be caused by faulty sensors, wiring problems, airflow restrictions, dirty filters, communication failures, or unstable electrical supply.
What are the most common LG AC error codes?
CH 01 (communication error), CH 05 (outdoor communication failure), CH 10 (fan motor issue), and CH 38 (refrigerant leak detection) are among the most frequently reported LG air conditioner errors.
Can I continue using my LG AC when an error code appears?
It is generally not recommended. Continued operation may cause additional damage to components such as the compressor, fan motor, inverter board, or control system.
When should I call a technician for LG AC errors?
Professional service is recommended for compressor faults, refrigerant leaks, PCB failures, electrical issues, or any error code that returns after a power reset.
Why is my LG air conditioner not cooling properly?
Check air filters, thermostat settings, airflow restrictions, and outdoor unit condition. Dirty coils or low refrigerant levels can also reduce cooling performance.
Why does my LG AC shut off unexpectedly?
The unit may shut down due to overheating protection, sensor faults, communication errors, voltage issues, or compressor protection functions.
What causes LG AC communication errors?
Communication errors are commonly caused by damaged wiring, loose connectors, faulty control boards, power interruptions, or communication cable failures between indoor and outdoor units.
How do I reset my LG air conditioner?
Turn off the unit, disconnect power for approximately 5–10 minutes, then restore power and restart the system. This may clear temporary fault codes.
Why is my LG AC making unusual noises?
Unusual noises may be caused by loose panels, fan motor issues, airflow obstructions, compressor problems, or debris inside the indoor or outdoor unit.
What does CH 10 mean on an LG air conditioner?
CH 10 indicates an indoor fan motor problem. Inspect the fan motor, wiring connections, and fan blade movement. Replace faulty components if necessary.
How can I prevent LG AC error codes?
Regularly clean air filters, maintain proper airflow, inspect wiring connections, keep outdoor coils clean, and schedule routine maintenance to reduce the likelihood of error codes.
Important: If the LG air conditioner continues to display error codes after troubleshooting, turn the unit OFF, disconnect power, and contact a qualified LG air conditioning technician. Continuing operation with active faults may cause damage to the compressor, control board, sensors, or other critical components.