Central air conditioners are widely used by office, supermarket and other big buildings. The evaporator, condenser and compressor are the main parts of the air conditioner. And the compressor plays a critical role in the cooling process because it is the middle-man between the evaporator and the condenser. The function of compressor is to convert the low-pressure, gaseous refrigerant from the evaporator into a higher pressure, higher temperature gas before it enters the condenser. That is how the compressor works in the system. Compressor for central air conditioner unit also plays its core role in the central air conditioner system. The refrigerant is a low-pressure gas when it leaves the evaporator. In order to release the heat the refrigerant absorbed, the refrigerant needs to be of a higher temperature than the air outside. That’s how the compressor to do its work.