LG Heat Pump Error Code E414

E414 indicates an outdoor unit SUMP DOWN 2 protection control event. This means the system has detected conditions suggesting refrigerant may have migrated into the compressor oil sump, creating a risk of compressor damage on startup. The heat pump activates this protection to prevent the compressor from running under unsafe lubrication conditions. A technician should inspect the sump heater, refrigerant charge, and compressor temperature sensors to identify the root cause.

You should not attempt to force the system to run while E414 is active. The protection control exists specifically to prevent compressor damage from refrigerant flooding the oil sump. Running the compressor under these conditions can cause severe internal damage, potentially requiring a full compressor replacement. Leave the unit in its protected state until a technician has cleared the fault.

Repair costs depend heavily on the root cause. Replacing a sump heater typically falls in the range of $150 to $400 including labor. A refrigerant charge adjustment can range from $100 to $300 depending on the amount of refrigerant involved. Compressor temperature sensor replacement generally runs $150 to $350. If the control board requires replacement, costs can range from $400 to $900 or more depending on the specific outdoor unit model.

Most causes behind E414 require professional diagnosis and tools. Checking refrigerant charge requires EPA-certified equipment and handling, and verifying sump heater voltage involves working inside the outdoor unit with live electrical components. A qualified HVAC technician is strongly recommended to safely diagnose and resolve this error.

A power reset may temporarily clear the error display, but if the underlying cause such as a failed sump heater, refrigerant overcharge, or sensor fault has not been corrected, the E414 code will return. In some cases the sump protection may re-engage quickly after restart if sump conditions are still outside acceptable limits. Resetting without diagnosis is not a permanent fix.