LG Air Conditioner Error Code E457

E457 indicates that the outdoor unit has detected its fan operating in a reversed wind direction. The system monitors airflow and fan motor behavior, and when it determines the fan is moving air opposite to the expected direction, it triggers this error code. The unit will typically shut down to prevent efficiency loss and potential component damage from improper heat exchange.

No, you should not attempt to continue running the unit while E457 is active. A reversed outdoor fan direction means the system cannot properly reject or absorb heat, which places excessive stress on the compressor and can lead to high-pressure faults or compressor failure. Leave the unit off until the fault is diagnosed and corrected.

A power reset may temporarily clear the error code and allow the unit to restart, but if the underlying cause such as a faulty motor, bad capacitor, or wiring issue is still present, the error will return quickly. Resetting without repairing the root cause risks further damage to the compressor and control components. A proper diagnosis should be performed before returning the unit to normal operation.

Some causes, such as reversed wiring connections made during a recent service visit, may be correctable by a knowledgeable DIYer who can access the outdoor unit wiring and compare it against the unit's wiring diagram. However, diagnosing motor faults, testing inverter board outputs, and replacing components like the fan motor or control board typically requires professional tools and expertise. It is recommended to contact a qualified HVAC technician for a full diagnosis.

Repair costs depend on the root cause. A simple wiring correction may only involve a service call fee, typically in the range of $75 to $150. Replacing a run capacitor generally costs between $80 and $200 including labor. A fan motor replacement can range from $200 to $500 or more depending on the model, and an inverter board or motor driver replacement can range from $300 to $700 or higher for parts and labor.