An AC compressor is a mechanical device that compresses refrigerant gas, which is then circulated through the AC system to produce cool air. The compressor is driven by the engine's serpentine belt and is responsible for compressing the refrigerant gas into a high-pressure state. Once the refrigerant reaches a high enough pressure, it then passes through the condenser, where it is cooled by the outside air before entering the evaporator.

The cost to replace an AC compressor can vary depending on several factors. The make and model of your vehicle will play a large role in the cost, as well as the type of compressor needed for replacement. On average, the cost of a replacement AC compressor can range from $500 to $1000. This cost can increase if additional components need to be replaced, such as the condenser or evaporator.