A/C System Operation: Notes

The temperature in the passenger compartment depends on the amount of heat radiated through the windows and conducted by the metal parts of the body. In hot weather it is possible to achieve a more comfortable temperature for the passengers by drawing off some of the heat.

As heat spreads into cooler areas, the passenger compartment is equipped with a unit for generating low temperatures. In the unit, refrigerant is constantly being evaporated. The heat required for this is extracted from the air flowing through the evaporator.

After absorbing the heat, the refrigerant is pumped through the A/C compressor. The compression action of the A/C compressor increases the heat content and temperature of the refrigerant. Its temperature is then substantially higher than that of the surrounding air.

The hot refrigerant flows to the condenser. There, the refrigerant releases its heat through the condenser to the surrounding air due to the temperature difference between the refrigerant and the air.

The refrigerant thus acts as a heat transfer medium. Since it is to be reused, the refrigerant returns to the evaporator.

For this reason, all A/C systems are based on the refrigerant circulation principle. However there are differences in the makeup of the assemblies.