How do you recharge an airplane Air Conditioner?

Answer 1

An airplane airconditioner is completely different than the one in your house or car. It doesn't rely on a refrigerant. Rather it takes hot high pressure air from the hot compressor section of the turbine engine and puts into something called a PAC. There is one PAC for each engine. The air first goes into a heat exchanger where it is cooled by ram air. Some of the air is then sent to a small turbine where the pressure is further increased. the air is then cooled again through another heat exchanger then sent to an expansion turbine where the pressure is dropped, rapidly cooling the air. A water separator collects the water released from this rapid expansion. The resulting cold air is then mixed with the air that was sent to the first heat exchanger. The pilot manually adjusts the mixing of the two air supply's to arrive at a temperature that is suitable for the cabin. The temperature is voice controlled. When the flight attendant calls up and yells it's too hot back here, he knows it's time to readjust. Since there are two PAC's one is used to control the air in the front of the airplane, the other the rear. People in the middle get what's left over... Hope this helps. -- Southwest Airlines First Officer ( aka "termperature boy")