What is an AC compressor?
The air conditioning compressor moves refrigerant through the AC system and compresses low-pressure refrigerant to create high-pressure refrigerant.

How does the AC compressor work?
The serpentine belt or drive belt runs the AC compressor, allowing it to pressurize refrigerant and pass it on through the system. The compressor also uses check valves and other moving parts that allow refrigerant to flow in one direction.
What are the symptoms related to a bad AC compressor?
When the
compressor fails, the most common symptom is warm air from the vents. A squealing or grinding noise may also be heard from the compressor in the event of mechanical failure.
Can I drive with an AC compressor problem?
In most cases, a vehicle with a bad air conditioning compressor is safe to drive.
However, if grinding is heard from the compressor pulley, bearing failure may occur, causing the serpentine belt to come off. If this occurs, the battery warning light will illuminate, and the engine will stall due to lack of electrical power.
How often do AC compressors need to be replaced?
Failure of the air conditioning compressor is common because moisture or clogs in the system will place stress on the compressor.
Compressor clutch failure is much more common on older vehicles. In general, AC compressors tend to fail after 60,000 to 70,000 miles, but that time may vary depending on use, demand and operating conditions.
How are AC compressor issues diagnosed?
Diagnosing the compressor requires advanced knowledge of air conditioning systems. AC systems should be repaired by a technician with proper training and certification. Professional-grade equipment is used to read the pressure, and the technician must rely on hours of classroom and training to diagnose the faulty part.
How is an AC compressor replaced?
Replacement of most air conditioning components requires the complete evacuation of the air conditioning system. The serpentine belt, refrigerant lines and electrical connectors must be removed. Finally, the mounting bolts and hardware must be removed to let the compressor come free from the engine.
A new compressor will then be installed, all parts will be put back in place, and the AC system will be recharged with refrigerant.
RepairPal recommendations for AC compressor issues
Refrigerant is environmentally harmful, and should never be released into the air. Instead, a proper refrigerant recovery machine must be used.
Can I replace the AC compressor myself?
Repair of AC components should be left to certified professionals, and is not considered a DIY job.