Glossary

AFUE% - Annual Fuel Utilization Efficiency. A measure of a furnace's heating efficiency. The higher the AFUE%, the more efficient the product. The government's established minimum AFUE rating for furnaces is 78%.

Air Handler - The portion of the central air conditioning or heat pump system that moves heated or cooled air throughout a home's ductwork. In some systems a furnace handles this function.

Balance Point - An outdoor temperature, usually between 30° F and 45° F, at which a heat pump's output exactly equals the heating needs of the home. Below the balance point, supplementary electric resistance heat is needed to maintain indoor comfort.

Btu - British thermal unit. The amount of heat required to raise the temperature of one pound of water (about one pint) by one degree F.

Evaporator Coil - The portion of a heat pump or central air conditioning system that is located in the home and functions as the heat transfer point for warming or cooling indoor air.

Heat Pump - An air conditioner that contains a valve that allows it to alternate between heating and cooling.

Heat Source - A body of air or liquid from which heat is collected. With York heat pumps, the air outside the home is used as the heat source during the heating cycle.

HSPF - Heating Seasonal Performance Factor. A measure of a heat pump's heating efficiency. The higher the HSPF, the more efficient the product. There is no government established minimum HSPF rating for heat pumps.

Outdoor Coil/Condensing Unit - The portion of a heat pump or central air conditioning system that is located outside the home and functions as a heat transfer point for collecting heat from and dispelling heat to the outside air.

SEER - Seasonal Energy Efficiency Ratio. A measure of an air conditioner's cooling efficiency. The higher the SEER, the more efficient the product. The government's established minimum SEER rating for air conditioners is 10.

Single Package - A year-round heating and air conditioning system that has all of the components completely encased in one unit outside the home.

Split System - A heat pump or central air conditioning system with components located both inside and outside the home. The most common design for home use.

Supplementary Heat - The auxiliary or emergency heat, usually electrical resistance heat, provided at temperatures below a heat pump's balance point.