To use the compressor to pump all of the system's refrigerant into the receiver and/or condenser prior to opening the system for service. This is also used in commercial systems to prevent refrigerant migration in the off cycle.

80% of the fuel burned is turned into heat delivered at the register. The U.S. government's established minimum AFUE rating for a furnace is 78 percent.

A heat exchanger consisting of two diagonal coils that are joined together in the shape of the letter A.

A storage tank located in the suction line of a compressor.

Stands for Air Changes per Hour. It is the number of times in one hour that the air in your house is completely replaced with outside air.

The presence of corrosive substances in a sealed refrigeration system.

Installing a heat pump in conjunction with an existing fossil fuel furnace. The result is a dual fuel system.

A rating that reflects the efficiency of a gas furnace in converting fuel to energy. A rating of 90 means that approximately 90% of the fuel is utilized to provide warmth to your home, while the remaining 10% escapes as exhaust.

A substance capable of causing an allergic reaction because of an individual's sensitivity to that substance

Inflammation of the mucous membranes in the nose that is caused by an allergic reaction.