LG Heat Pump Error Code rx

The RX code on an LG heat pump indicates that cooling operation has been automatically blocked because the outdoor temperature has dropped below -5°C (23°F). The display flickers to signal that this protection mode is active. It is a built-in safeguard designed to protect the compressor and refrigerant system, not a sign of a defect or component failure.

The RX code itself does not indicate a safety hazard. It is a protective feature that the system activates intentionally to prevent damage to the compressor under low ambient temperature conditions. The unit is functioning as designed when this code appears during cold weather.

If the RX code is triggered by actual cold outdoor temperatures, there is no repair cost involved since no parts or service are needed. If a faulty outdoor temperature sensor is the cause, sensor replacement parts and labor typically range from $75 to $250 depending on your location and service provider. A control board replacement, if needed, would generally cost more, ranging from $200 to $600 or higher.

In most cases, no repair is needed. Simply wait for outdoor temperatures to rise above -5°C, and the system will automatically clear the restriction and resume cooling operation. If the code appears when outdoor temperatures are clearly above the threshold, have a technician inspect the outdoor temperature sensor and its wiring for faults.

Resetting the unit will not permanently clear the RX code if the outdoor temperature is still below -5°C, because the control board will reactivate the protection lockout as soon as it reads the temperature again. The code will only clear and stay clear once the outdoor temperature rises above the threshold, or if a faulty sensor causing a false reading is replaced.