Learn the value of AFUE ratings

AFUE stands for Annual Fuel Utilization Efficiency. AFUE is a measurement of the amount of heat an appliance produces in relation to how much energy it consumes in a year. The Federal Trade Commission (FTC) requires all new furnaces and boilers to display their AFUE ratings on a highly visible label so that consumers can easily compare the energy-efficiency of different units.

An AFUE percentage is a calculation of heat produced over energy consumed. A furnace that has an 80% AFUE rating, for example, can turn 80 percent of the energy it consumes into heat. The rest is lost in the process

The current minimum AFUE rating allowed for new furnaces is 78%. According to the Environmental Protection Agency (EPA), a middle-grade unit has an AFUE rating around 80%, while a high-efficiency unit has a rating between 90% and 97%

High-efficiency furnaces devour tremendously less energy than low-efficiency units. Over the years they will save you a great deal of money on your energy bills. High-efficiency furnaces also leave a smaller carbon footprint than less efficient units.

The only disadvantage of high-efficiency furnaces is that the upfront cost can cause a bit of a sticker-shock. If you happen to upgrade from an old furnace with a very low AFUE rating, the ROI will be seen almost immediately.

NOTE: Buyer beware. There have been many instances where manufacturers have stretched their AFUE rating and later been in trouble with the FTC and EPA. Do your research and trust your local HVAC technician to give you good recommendations.