LG Heat Pump Error Code P702

P702 means the heat pump has shut down the compressor because the high pressure sensor detected a dangerously elevated refrigerant pressure level, triggering protection control 2. This is a safety lockout designed to prevent compressor and refrigerant system damage. The root cause needs to be identified and corrected before the unit can safely return to normal operation.

No. The P702 lockout exists specifically to protect the compressor from running under unsafe high pressure conditions. Continuing to operate the unit or repeatedly forcing it to restart without addressing the underlying cause can lead to compressor failure, refrigerant line rupture, or other serious damage. The system should remain off until the cause is diagnosed and corrected.

Repair costs vary significantly depending on the root cause. A coil cleaning or filter replacement is relatively inexpensive, typically in the range of $75 to $200 for a service call. Refrigerant system work such as recharge or evacuation can range from $150 to $500 or more. Replacing components like an expansion valve or high pressure sensor generally falls in the $200 to $600 range depending on parts and labor rates in your area.

Some basic checks, such as cleaning the outdoor coil, clearing debris from around the unit, and replacing a clogged air filter, can be done by a homeowner and may resolve the fault if restricted airflow was the cause. However, diagnosing refrigerant charge issues, testing the high pressure sensor, or replacing components like an expansion valve requires a licensed HVAC technician with proper tools and refrigerant handling certification. Attempting refrigerant work without certification is both illegal and dangerous.

A power reset may temporarily clear the P702 code and allow the unit to restart, but if the underlying cause is not corrected, the high pressure condition will return and the system will lock out again, potentially with greater severity. Resetting without repair is not a solution and risks accelerating component damage. The fault should be fully diagnosed before restoring power.