LG Heat Pump Error Code E432

E432 on an LG heat pump means the unit is blocking cooling mode operation because the outdoor ambient temperature has been detected at or below -5°C (23°F). This is a built-in protection specification designed to keep the system from operating in cooling mode under conditions that could damage the compressor or refrigerant circuit. It is not an indication of a broken component in most cases. The unit should resume normal cooling operation once outdoor temperatures rise above the threshold.

The E432 code indicates the unit is actively preventing cooling mode operation, so attempting to force cooling in these conditions is not recommended. The protection threshold exists because running cooling mode at very low outdoor temperatures can stress the compressor and affect refrigerant pressures beyond their safe range. If you need heating, heating mode is not restricted by this code and should remain available.

If the code is triggered by genuinely cold weather, the cost is nothing since no repair is needed. If a faulty outdoor ambient temperature sensor is responsible, sensor replacement parts typically range from around $20 to $80 depending on the model, with professional labor adding $75 to $200 depending on local rates. If control board replacement is ultimately required, costs rise significantly and can fall in the range of $200 to $600 or more for parts and labor.

Start by checking the actual outdoor temperature with an external thermometer. If it is genuinely below -5°C, no fix is needed since the unit is operating correctly and the code will clear once temperatures rise. If outdoor temps are above -5°C and the code persists, have the outdoor ambient temperature sensor tested for correct resistance and inspect the sensor wiring for damage or corrosion. A faulty sensor will need to be replaced to resolve a false lockout.

A manual reset will temporarily clear the code display, but the E432 will return immediately if the outdoor temperature sensor still reads below -5°C. The lockout is continuously evaluated by the control board, so the underlying condition must change for the code to stay cleared. If the outdoor temperature is genuinely cold, the only resolution is waiting for warmer weather.