a compressor when it starts it pump freon gas through a sealed system and suck it back into the compressor completing the cycle.

the sealed system consists of the

compressor

condenser

filter/drier

capillary tube

evaporator

the compressor pump the gas through the condensor first at this point the gas is hot the condensor is mostly cooled by a fan sometimes it is on the back of older refrigerators,then the gas pass through a filter/dryer then it goes through a capillary the capillary is a very small tube that look like a wire, when the gas pass through this small tube it make the change from hot to cool, it enters the evaporator which is a larger tube, the evaporator is situated inside the freezer compartment of the refrigerator---there are other things that help to make the refrigerator work--like fan motors--thermostats--heaters--and relay and overload and other switches, defrost timer and defrost thermostat.

New refrigerators now have electronic controls and sensors and even though you still plug them in the regular plug they use different voltage at different components,for example you might have 125 ac volts at the compressor,you could have 10--2.5 and 3 dc volts at the evaporator fan motor, if the fan motor is a 3 speed motor.

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