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What Is My Furnace’s AFUE and How Can It Save Me Money?

furnace tips and definitions

If you’re shopping around for a new furnace you’ve probably noticed they’re all given different “AFUE” ratings.

So, what exactly is this rating and how does it affect you?

Well, a furnace’s AFUE rating, or the Annual Fuel Utilization Efficiency rating, does 2 things:

  • It measures how energy-efficient your furnace is
  • It determines how much money you’ll save on monthly heating costs (the higher the rating, the more money you’ll save each month)

Now let’s dig a little deeper and take a look at how your furnace’s AFUE rating does those 2 things...

Still not entirely sure that you need a new furnace yet? Check out our blog, “Do I Need A New Furnace? 5 Signs That Point to Yes” to help you decide.

AFUE: Ratio of fuel used to fuel wasted

So, we already know that the AFUE rating of a furnace measures how “energy-efficient” that unit is. But what exactly does “energy efficient” mean when it comes to furnaces and how is that measured?

The AFUE rating looks at how efficiently a furnace converts its fuel into heat. The rating compares how much heat the furnace puts out yearly to how much fossil fuel it consumes yearly.

So, for example, a furnace with an AFUE rating of 80 means:

  • 80% of the fuel it consumed was turned into heat energy
  • 20% of the fuel it consumed was wasted (escaped up the furnace flue)

Now let’s look at the part we know you’re really interested in: the savings.

How does AFUE translate into savings?

Like we mentioned earlier, the higher the AFUE rating, the more money you’ll save on monthly heating costs.

Think of it this way: imagine you have a furnace with an AFUE of 80. For every $100 you spend on heating, $80 of that $100 was actually used to heat up your home while the other $20 was wasted.

Newer gas furnaces come with AFUE ratings as high as 98.5 while the minimum AFUE rating you can get today is around 80.

But if your home has an older furnace, it could very well have an AFUE as low as 60. 

Want an idea of exactly how much you’ll save by upgrading to a higher AFUE furnace?

This furnace savings calculator allows you to enter your current furnace’s AFUE alongside the AFUE of a more efficient furnace to show you exactly how much you’d save. 

Have more furnace questions? Ask a Minneapolis tech

When buying a new furnace, the AFUE rating is important but there are many other features to consider such as:

  • The size 
  • System type
  • Fuel source
  • Warranty
  • Etc.

To help you navigate the world of furnaces, check out our article, “A Beginner’s Guide to Purchasing the Perfect Furnace for Your Home”.

Want in-person, professional advice on the furnace that would best fit your needs?

Contact MSP today, our techs will give you the honest and knowledgeable advice you need to make the best purchase.

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Categories: Heating