Proper Operation
Learn how your appliance is supposed to operate so you can determine if it is malfunctioning.

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Refrigeration Cycle (Moving Heat)

Condensor Coils

Condenor coils

Your refrigerator draws heat from the freezer section's evaporator coils and dumps it out into the ambient air from the condensor coils. The evaporator coils, the compressor and the condensor coils are filled with refrigerant (R-12) gas. The compressor is the "heat pump". It draws the expanded gas from the evaporator coils and compresses it into a saturated liquid and gas which is pumped into the condensor coils. The saturated gas entering the condensor coils is hot (over 120 deg F) and under pressure. As the gas moves through the coils it gives up its heat by radiating it to the cooler ambient air outside the coils. The condensor fan speeds up the radiation of heat by blowing ambient air over the condensor coils. In fact, if the condensor fan doesn't help move the warm air away from the coils underneath the refrigerator, the freezer section won't get much below freezing. The diagram to the right shows the condensor coils along with the compressor and the condensor fan on the bottom of a refrigerator.

Evaporator Coils and Fan

Evaporator coils

When the saturated refrigerant gas leaves the condensor coils, it has given up most of its heat and it moves up a thin copper pipe called a capillary tube to the evaporator coils. The gas is still under pressure in the capillary tube but when it enters the evaporator coils it expands rapidly because the pressure in the evaporator coils is very low. When the refrigerant gas expands, it absorbs heat from the surrounding coils. The surface temperature of the evaporator coils are normally below 0 degrees F. After the gas has absorbed the heat of expansion, it is sucked out of the evaporator coils by the compressor and the refrigeration cycle is complete. The evaporator fan is essential for moving the cold air. The evaporator fan carries the cold air away from the coils and distributes it to the freezer and refrigerator sections. The diagram to the right shows the evaporator coils and the evaporator fan.