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Comfort of vehicle occupants > < Properties of refrigerant oil
How air conditioning works
How air conditioning works
The temperature in the passenger compartment depends on the amount of heat radiated into the vehicle through the windows and conducted by the metal parts of the body. In hot weather some of the heat must be pumped off to achieve a more comfortable temperature for the occupants.
As heat is always transmitted away from warmer areas and into cooler areas, the passenger compartment is fitted with a unit for generating low temperatures in which refrigerant is constantly evaporated. The heat required for this is extracted from the air flowing through the evaporator.
After absorbing heat, the refrigerant is pumped off by the air conditioner compressor. The work of compression of the air conditioner 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 with its heat content to the condenser. where the refrigerant dissipates its heat to the surrounding air via the condenser due to the temperature gradient between the refrigerant and the surrounding air.
The refrigerant thus acts as a heat transfer medium. As it is re-used, the refrigerant is returned to the evaporator.
For this reason all air conditioning systems are based on the refrigerant circulation principle. There are however differences as regards the units used.
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Comfort of vehicle occupants > < Properties of refrigerant oil