LG Air Conditioner Error Code E422

E422 on an LG air conditioner indicates an EEV or valve close error, triggered by the unit's self-diagnosis system detecting that refrigerant flow is restricted. The system has identified a condition consistent with a clogged or closed outdoor service valve. The unit shuts down automatically to prevent compressor damage from abnormal refrigerant pressure conditions.

No, you should not attempt to bypass or continue operating the unit while E422 is active. The error indicates restricted refrigerant flow, and running the compressor under these conditions can cause overheating, compressor damage, or high-pressure faults. Leave the unit off until the root cause has been identified and corrected.

Repair costs vary depending on the cause. If the fix is simply opening a closed service valve, a technician visit may cost between $75 and $150 for the diagnostic and labor. If the EEV itself needs to be replaced, total costs including the part and labor typically range from $300 to $700 or more depending on the model and local labor rates.

Start by locating the outdoor unit and inspecting the service valves, which are typically capped brass fittings on the refrigerant lines. Confirm that both the liquid and suction service valves are fully open. If the valves are already open, the issue may be a faulty EEV, a refrigerant circuit blockage, or a control board problem, all of which require a licensed HVAC technician to diagnose and repair.

A power reset may temporarily clear the error display, but the code will return if the underlying cause has not been resolved. If the service valve is closed or the EEV is faulty, those conditions will persist through any reset. Address the physical cause before attempting to resume normal operation.