What is AFUE (Gas Furnaces only)?
AFUE is an abbreviation for Annual Fuel Utilization Efficiency ratio. AFUE is used to rate furnace efficiencies by dividing the ratio of heat output to heat input. This measure tells you how well your furnace is burning the fuel it is being supplied with. As the AFUE increases the efficiency of you furnace increases there by lowering the fuel costs. Furnaces manufactured in the US are required to at least have an efficiency of 80% or more. A furnace that is rated at 80% will use that percentage fuel and the other 20% percent is wasted. So the higher the percentage the more efficient the furnace will be. What is HSPF (Heat Pumps only)? HSPF is the abbreviation for the Heating Seasonal Performance Factor. This factor rates the efficient operation of the heating portion of the heat pump. As the HSPF increases, the unit functions at a more efficient level. New units in the United States have HSPF ratings from 7.0 to 9.4. The higher the number the more efficient the heat pump will be. What
