All of the mentioned components are linked via a series of hoses and pipes (tubing).

Lets begin with the compressor which draws low pressure gas from the evaporator and compresses it into high pressure gas. When compressed, the gas gets hot. The hot gas travels to the condenser where the cool air passing over the fins and coils dissipates much of the heat. As the gas cools, it condenses into a high pressure liquid and collects in the receiver drier or in the liquid line (remember, there is also an accumulator system), and is made available for entry into the evaporator via the metering device which may be an expansion valve or an orifice tube. When the liquid reaches the metering device it is restricted which causes a pressure drop on the other side of the device. The Freon enters the evaporator as low pressure liquid. The low pressure causes the liquid to evaporate or boil and turn to gas. Meanwhile, a fan is moving passenger compartment air over the coils of the evaporator and the now gaseous Freon collects heat from that air. The now heated gas is then drawn back into the compressor and the cycle repeats itself.

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