What Is AFUE?

Posted: June 19, 2018

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We use a lot of acronyms in the home heating business, but some are more important than others.

Take AFUE, for example.

AFUE stands for Annual Fuel Utilization Efficiency: the higher the AFUE rating, the more efficient your heating equipment is (kind of like miles per gallon for your car).

AFUE is used to illustrate the energy efficiency of heating oil appliances, including furnaces, boilers, and water heaters. The AFUE number (usually displayed on a yellow sticker on the unit) represents how much of the fuel your equipment consumes is directed toward actually generating heat (as opposed to how much energy is wasted along the way).

For example, in an 85 AFUE unit, 85 percent of the fuel consumed by the machine goes to heating your home; the remaining 15 percent is lost in transit – usually up the chimney. In 2015, the US government raised the minimum AFUE rating on furnaces from 78 to 80 percent; oil-fired boilers are required to produce an AFUE rating of 84 percent.

One way to think about AFUE is to consider it in terms of dollars: For every dollar you spend on fuel for an 85 AFUE furnace, 85 cents goes toward heating your home. If your furnace is old and not well maintained, your AFUE could drop into the 60s or even 50s – a big reason why the decision to replace your furnace or boiler often pays for itself pretty quickly.

Of course, AFUE doesn’t tell the whole efficiency story – proper heating system installation and heating system maintenance are also extremely important pieces of the equation, as are several other factors. But knowing the AFUE rating of your heating equipment is important when it comes time to invest in new high efficiency heating equipment for your Rhode Island home.

Looking for an energy efficient replacement for your furnace, boiler, or water heater? We can help! Contact us today for a FREE, no obligation estimate on a unit that’s sized for your home, budget, and lifestyle.