Evaporator Coil
The coil containing the cold freon liquid over which the warm air from the interior of the home is passed.  The heat from the air is absorbed by the freon liquid in the coil cooling the air but causes the freon to boil and turn into a gas.  The coil gets its name because the freon in the coil evaporates or turns into a gas when it absorbs the heat from the air passing over the coil.  The location and use of the coil may indicate the type of air conditioning system.  An evaporator coil that is incorporated into a warm air furnace is called a split system.  An evaporator coil that is used to warm air is called a heat pump.  An evaporator coil that is not part of a heating system is an independent system.

Compressor
Compresses the freon gas to increase its temperature.  The compressor is needed to make the temperature of the gas much higher than the temperature of the air outside the home.  The compressor is the main device that moves the freon through the system and is usually located next to the condensing coil.

Condensing Coil
The coil containing the high pressure and high temperature freon over which air on the exterior of the home is passed.  The air on the exterior of the home absorbs the heat from the freon in the coil.  As the high pressure freon gas loses heat, it turns back into a liquid.  The coil gets its name from the freon condensing or turning back into a liquid.  Condensing coils are generally cooled by air, however, some systems use water to absorb the heat from the coil.

Blower
Fan used to move the warm air from the interior of the home, over the evaporator coil to be cooled, then back into the home.

Condensate Tray and Line
Captures the moisture that develops on the evaporator coil as the air in the home is cooled.  The line directs the water to a plumbing drain.