LG Multi V VRF System Error Codes
LG Multi V VRF systems display fault codes as CH (Check) codes on the remote controller or LGAP controller. CH codes are two-digit numbers. Codes can be read on the outdoor unit LED (flashes) or via LG HVAC Solution (cloud diagnostic tool).
Multi V Fault Code Table
| Code | Fault Description | Common Cause | Action |
|---|---|---|---|
| CH01 | Indoor unit sensor fault | Intake or pipe sensor failure | Check sensor resistance |
| CH02 | Pipe sensor fault (indoor) | Liquid or gas sensor failure | Check thermistor |
| CH03 | Fan motor fault (indoor) | Indoor fan motor failure | Check motor and capacitor |
| CH05 | Communication error | Indoor-to-outdoor wiring | Check communication wiring |
| CH10 | Indoor PCB fault | Control board failure | Replace indoor PCB |
| CH21 | Inverter over-current | Compressor or inverter board | Check compressor winding |
| CH22 | Inverter fault | Inverter PCB failure | Check DC bus, replace inverter |
| CH26 | High discharge temp | Low refrigerant, blocked EEV | Check charge and EEV |
| CH27 | High pressure | Dirty outdoor coil, overcharge | Wash coil, check charge |
| CH29 | Low pressure | Low refrigerant, EEV fault | Check charge and EEV |
| CH34 | Outdoor PCB fault | Outdoor control board failure | Replace outdoor PCB |
| CH38 | EEV fault | Electronic expansion valve | Check EEV operation |
| CH45 | Compressor overload | Compressor protection trip | Check amps, check voltage |
| CH67 | Outdoor fan motor fault | Fan motor or PCB driver failure | Check motor amps |
Most Common Multi V Faults
CH05 - Communication Error
LG Multi V uses a 2-wire communication bus between indoor and outdoor units. Check for miswired connectors, damaged cable, or address conflicts. On multi-outdoor configurations, check inter-unit communication as well.
CH26 - High Discharge Temperature
Discharge temperature above 250 degrees F (121 degrees C) triggers CH26. Check refrigerant charge using LG’s DX charging chart. Also check EEV operation - a stuck-closed EEV causes high discharge with low suction pressure.
CH27 - High Pressure
On Multi V units, HP switch is set at 590 psi (R-410A). Dirty outdoor coil, restricted airflow, or overcharge are typical causes. Verify all outdoor unit fans are operating.
CH21 - Inverter Overcurrent
Check compressor winding resistance with ohmmeter (all phases should be equal, typically 0.5-2 ohm). Measure DC bus voltage at inverter. Check inverter board LED status for secondary fault indication.
Parts Commonly Needed
| Part | Notes |
|---|---|
| Outdoor PCB | Match Multi V model exactly |
| Indoor PCB | Match indoor unit model |
| EEV (electronic expansion valve) | Match valve size and refrigerant |
| Outdoor fan motor | DC motor type on most Multi V |
| Communication cable | 2-wire shielded - check polarity |
Need Replacement Parts?
Before ordering, match the HVAC part to the model number, electrical rating, and failure symptom. Check current prices on Amazon - prices and availability change frequently.
Pro tip: LG Multi V systems can be diagnosed remotely via LG HVAC Solution. Register the system with the ACS (Advanced Central System) for real-time monitoring and fault code alerts without site visits.