Your vehicle's air conditioning system operates on the same principle as your home's refrigerator; extract heat and humidity from inside a sealed space and leave cold air in its place.
An ac unit consists of the following components:
The compressor pressurizes the refrigerant and sends it to the condensing coils (usaully located in front of the radiator). Compression causes the gas to heat. The condenser combines the additional heat with the heat the refrigerant picked up in the evaporator and transfers it to the air passing over it from outside the car. When the refrigerant cools down to its "saturation-point" temperature, it changes back from a gas into a liquid (this gives off a blast of heat called as the "latent heat of vaporization"). The liquid refrigerant then goes through the expansion valve to the evaporator coils, where it loses the pressure that was acquired in the compressor. Some of that liquid will change to a low-pressure gas as it cools the remaining refrigerant. This two-phase mixture enters the evaporator, and the liquid component of the refrigerant will absorb the heat from the air moving across the coil and then evaporate. Finally, a blower pushes air across the cold evaporator to cool the passenger compartment.
Golden State Transmission and Muffler 10792 Olson Dr., Rancho Cordova, California 95670 916.853.1788