When you schedule a heating inspection for your home, one of the things the heating contractor will check is your furnace’s efficiency. To understand your results—and to determine if you need a replacement—you should know what furnace efficiency ratings are and what they mean.

What Do Furnace Efficiency Ratings Mean?

Furnace efficiency ratings are displayed as a percentage, called an annual fuel utilization efficiency, or AFUE. It measures how much of the fuel required to run the furnace is actually converted to heat. The Federal Trade Commission requires new heaters to display their efficiency so you can understand each model’s impact.

For example, if your furnace has an 80% efficiency rating, then 80% of the fuel used is being converted to heat for your home. The rest of it escapes through the flue or vents.

Why They’re Important

Efficiency ratings matter because they affect the environment and your wallet. A low-efficiency rating (anything below 70% AFUE) means that you’re burning fuel without capturing heat. You’ll pay more in energy bills and have a larger carbon footprint because you need more fuel for the same amount of heat. The EPA considers anything with an AFUE of 90% or above to be highly efficient.

A low AFUE can indicate a need for furnace repair. If you buy a furnace that claims an 85% AFUE, but your heating inspection results say it’s running at 70%, then there’s a problem somewhere. Air leaks, faulty heating elements, or a clogged chimney are a few potential causes for this, and you’ll need furnace repair or replacement to have them fixed.

Have you had a heating inspection to test your furnace’s efficiency lately? Since 1994, the skilled heating contractors at Butler Heating & Air in West Plains, MO, has offered comprehensive furnace services. If your heating system isn’t doing the job, they’ll perform reliable repairs or help you install an affordable replacement. All of their technicians are NATE-certified, and they boast a welcoming and comfortable atmosphere. Learn more about their services online, and call (417) 256-7984 to schedule a heating inspection.