LG Heat Pump Error Code P733

P733 indicates that the outdoor unit's discharge temperature sensor 3 has detected a temperature high enough to trigger protection control. The system shuts down the compressor to prevent heat-related damage to internal components. This is a protective fault, not a simple nuisance trip, and it points to a real condition that needs to be investigated and corrected.

No. The P733 code is a protection control event specifically designed to prevent compressor damage from excessive heat. Continuing to operate the system or repeatedly forcing restarts while the underlying cause remains unresolved can lead to compressor failure, which is a costly repair. The unit should remain off until the fault is properly diagnosed and corrected.

Repair costs vary widely depending on the cause. A thermistor replacement is generally in the range of $100 to $250 including labor. A refrigerant recharge can range from $150 to $400 or more depending on refrigerant type and the amount needed. Fan motor replacement typically falls between $200 and $500. Compressor replacement is the most expensive scenario, often ranging from $1,000 to $2,500 or higher depending on the unit.

Some preliminary checks, such as cleaning the outdoor coil and confirming the fan is running, can be done by a knowledgeable homeowner. However, diagnosing refrigerant charge issues requires EPA-certified equipment and credentials, and replacing internal components like the discharge thermistor or fan motor requires technical skill. Most P733 causes are best handled by a qualified HVAC technician.

A power reset may temporarily clear the fault and allow the unit to restart, but if the root cause is still present, the P733 code will return, often quickly. Repeated resets without addressing the underlying issue risk accelerating compressor wear or damage. A proper repair is necessary for the error to stay cleared.