LG Air Conditioner Error Codes

Complete LG AC Troubleshooting Guide

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.
Important: If the error code continues after troubleshooting, disconnect the air conditioner from power and contact a qualified LG technician.