LG Heat Pump Error Code E405

E405 on an LG heat pump indicates an outdoor unit overload 2 protection control error. This means the system detected that the outdoor unit, most likely the compressor, was drawing excessive current beyond its safe operating limit. The protection circuit shuts down the unit to prevent damage to the compressor or electrical components. A technician should inspect the outdoor unit before attempting to restart the system.

No, you should not continue operating the heat pump while the E405 error is active. The overload protection circuit tripped for a reason, and bypassing or ignoring it risks burning out the compressor or causing an electrical fault. Keep the unit off until the underlying cause has been identified and corrected by a qualified technician.

Repair costs vary widely depending on the root cause. Cleaning the condenser coil or checking refrigerant charge may cost between $75 and $250 for a service visit. Replacing an overload protector or minor electrical component typically ranges from $150 to $400 including parts and labor. Compressor replacement, if that is found to be the cause, is a major repair that can range from $800 to $2,500 or more depending on the unit size and refrigerant type involved.

Some basic checks, like cleaning a dirty condenser coil or clearing debris blocking the outdoor unit, can be done by a homeowner and may resolve the fault if restricted airflow was the cause. However, diagnosing refrigerant charge issues, testing compressor windings, and replacing electrical components like overload protectors or control boards require certified technician expertise and proper tools. Attempting repairs beyond basic maintenance without proper training can be dangerous and may cause further damage.

A reset may temporarily clear the E405 code, but if the underlying cause is not addressed, the error will return, often quickly. Repeated overload trips can shorten compressor lifespan significantly. A reset is only appropriate after a known temporary condition, such as extreme ambient heat on a very hot day, and even then a professional inspection is recommended if the fault recurs.