What Does AFUE Mean?

If you have a furnace or boiler as the main source of heat in your Clinton Township home, you’ve probably heard the term AFUE mentioned before. But what exactly does it mean, and how does it pertain to your Michigan home?

Our highly skilled and trained Great Dane Heating and Air Conditioning professionals are here to answer and address all of your heating and cooling questions. Our experts aim to always provide the information you need so you can move forward with the best, most informed decisions on furnace installations, repairs, and maintenance.

What Is AFUE?

AFUE is an acronym for annual fuel utilization efficiency, and it’s a measurement used to determine how efficient a furnace or boiler is at converting the energy in fuel to heat. A higher AFUE rating indicates the furnace or boiler has greater energy efficiency.

What Is the Minimum AFUE Rating for New Furnaces?

New furnaces have a minimum standard AFUE rating of 78. If a mid-efficiency furnace has an 80 AFUE rating, it means 80 percent of the energy consumed is able to be converted into heat while the remaining 20 percent escapes during this process.

More heat could even be escaping because AFUE ratings do not take into account when there are leaks in the ductwork, which could result in a loss of up to 35 percent of the furnace’s output energy when ducts are located in unconditioned areas like the attic or garage, according to the US Department of Energy (DOE).

Is There a Minimum AFUE Rating for New Boilers?

The minimum AFUE ratings for new boilers is:

• 82 percent for gas-fired hot water boilers
• 80 percent for gas-fired steam boilers
• 84 percent for oil-fired hot water boilers
• 82 percent for oil-fired steam boilers
  

Some of these ratings will be changing in 2021, as the US DOE finalized new standards for residential boilers to raise minimum efficiency levels.

Boilers operate in either a condensing or non-condensing mode. Condensing boilers condense water vapor produced from exhaust gases and convert it into heat. These are considered more efficient and usually have AFUE ratings higher than 88 percent while non-condensing boilers have between 80 and 88 percent.

What Is an Ideal AFUE Rating for a Furnace?

Mid-efficiency furnaces typically have between an 80 and 85 percent AFUE rating. High-efficiency furnaces are considered to have an AFUE rating at or above 90 percent with the most energy-efficient furnaces having an AFUE rating of 97 percent or higher.

An ideal AFUE rating depends on how energy efficient you would prefer for your furnace to be. If energy efficiency is important to you, be sure to select a furnace with a higher AFUE rating.

Are Higher AFUE Ratings Beneficial?

Furnaces and boilers with higher AFUE ratings are beneficial to you because they offer greater efficiency when converting heat, which results in reduced energy costs. Heating and cooling expenses are responsible for a large portion of the average homeowner’s utility bill, so opting for a furnace or boiler with a higher AFUE rating could be a great investment when you want to lower your energy expenses. 

Reach out to one of our Great Dane Heating and Air Conditioning experts who can go over what will work best in your home.

Great Dane Is Here for Your Furnace and Boiler Needs

Whether you are considering to invest in a new, energy-efficient furnace or boiler, or have other heating and cooling needs, our Great Dane Heating and Air Conditioning professionals are here for you. We have been exceeding the expectations of our customers here in Clinton Township, MI, since 1999 and will continue doing so for years to come! Call us today at 586.790.2604 or request service online.