Samsung Air Conditioner Error Code P512

P512 means the compressor has been shut down by low pressure sensor protection control 3. The system detected that suction-side refrigerant pressure dropped to an unsafe level and turned off the compressor to prevent internal damage. This is a protective safety response, not a random fault, and it points to a real issue in the refrigerant circuit or airflow system that must be corrected before the unit will run normally.

No. The P512 code means the compressor has already been shut down by the system as a protective measure. Attempting to force the unit to run with low refrigerant pressure can cause compressor overheating, oil failure, and permanent mechanical damage. Leave the unit off until the underlying cause has been diagnosed and corrected.

Repair costs vary depending on the root cause. A refrigerant recharge after a leak repair can range from $200 to $600 or more depending on refrigerant type and system size. Expansion valve replacement typically runs between $150 and $400 in parts and labor. A low pressure sensor replacement is generally a lower-cost repair, often in the $100 to $250 range. A full diagnostic service call is usually required before any cost estimate can be confirmed.

Some basic checks, such as confirming service valves are fully open, cleaning a dirty evaporator filter or coil, and ensuring airflow is unobstructed, can be done without professional help. However, diagnosing and repairing refrigerant leaks, replacing an expansion valve, or verifying sensor accuracy requires manifold gauges and EPA-certified refrigerant handling. For most homeowners, a licensed HVAC technician is necessary to fully resolve this code.

A reset may temporarily clear the fault display, but the P512 code will return if the root cause, such as a refrigerant leak, restricted expansion valve, or airflow problem, has not been fixed. Repeated resets without repair can lead to compressor damage. Address the pressure issue first, then reset the unit to confirm the fault does not recur.