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166240010
TYPICAL REFRIGERANT CIRCUIT
Heat always flows from hot to cold and therefore, the ”heat load”supplied to the evaporator section by water
gives up its heat to the refrigerant which is at a temperature below the freezing point of water. This refrigerant
now passes through the heat exchanger back to the compressor, as a low pressure vapor.
This low pressure vapor is compressed in the compressor, as it leaves the compressor at a high pressure in va-
por form it enters the top of the condenser. The condenser has a rapid flow of cool air across it which removes
much of the heat from the hot refrigerant vapor.
As the vapor, passing through the condenser, loses heat it condenses back to a liquid since it is still under high
pressure and cooler than when it entered the condenser. The liquid refrigerant then passes through the drier/fil-
ter still under pressure and goes through the heat exchanger where further cooling takes place. As the refriger-
ant leaves the automatic expansion valve, the pressure has dropped, causing the refrigerant to vaporize and boil
off as it picks up heat in the evaporator and since the pressure is low, the refrigerant will be cold.
HEAT
EXCHANGER
EVAPORATOR
CONDENSER
COMPRESSOR
DRIER/FILTER
AXV
FIGURE 6. TYPICAL REFRIGERANT CIRCUIT