By: Patricia Cermignano

S.E.E.R., A.F.U.E. and H.S.P.F. You’ve heard the terms before, but do you know what each word means and what their significant differences are?


Seasonal Energy Efficiency Ratio, also known as S.E.E.R., is used to rate the cooling efficiency in heat pumps and air conditioning systems. S.E.E.R., which is indicated as a ratio, is the relationship between how much cooling efficiency is produced and how much electricity it costs to produce it. The higher the S.E.E.R. rating is, the more efficient the system will be at converting electricity into cooling power. The minimum and maximum S.E.E.R. ratings for any new air conditioning unit or heat pump installed by a HVAC contractor are as follows:

  • Air Conditioning:
    • Minimum S.E.E.R. of 13
    • Maximum S.E.E.R. of 26
  • Heat Pumps:
    • Minimum S.E.E.R. of 14
    • Maximum S.E.E.R. of 26


Annual Fuel Utilization Efficiency, also known as A.F.U.E., is used to rate the heating efficiency in furnaces and boilers. A.F.U.E., which is indicated as a percentage, states the amount of energy being converted to heat your furnace. For instance, an A.F.U.E. rating of 90 means that your house is heated 90% by fuel, while the remaining 10% leaves as exhaust with the combustion gases. Thus, the higher the A.F.U.E. rating is, the more efficient the system is. Please see below for three tiers ratings of how A.F.U.E. is measured.

  • Low Efficiency Heating System: 56%-70% AFUE
  • Mid-Efficiency Heating System: 80%-83% AFUE
  • High Efficiency Heating System: 90%-98.5% AFUE


Heating Season Performance Factor, also known as H.S.P.F., is used to rate the heating efficiency in heat pumps. Similar to S.E.E.R., H.S.P.F. is calculated in the same way, but instead of representing the ratio between the cooling power to the electrical input, it represents the ratio between the heating power to the electrical input. The minimum H.S.P.F. efficiency rating a heat pump can be is 8.2, and the maximum H.S.P.F. efficiency rating a heat pump can be is 10.2.

If you are in the market for getting a new HVAC system installed or if you are simply wondering whether your current HVAC equipment is efficient or not, please call Bob Cermignano Air Conditioning & Heating, Inc.’s office at 610-642-6323 or visit our website at www.bobsredtrucks.com for more details.