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Covenant Heating and Cooling Blog

AFUE Ratings for Furnaces: What Do They Mean?

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When shopping for a new furnace, there are a lot of things to consider. Many homeowners understandably focus on the upfront cost of purchasing a furnace and its installation cost. 

It’s easy to let this initial cost be the only thing you take into consideration when for many homeowners, a new furnace is a huge expense. The natural inclination will be to want to spend as little money as possible. 

But doing so could potentially cost you more money in utilities for the 10-15 years that you own it. Let’s look at some other factors to consider besides the purchase price when it’s time for furnace installation in Brentwood, TN.

“Miles Per Gallon”

One of the first things a consumer who’s shopping for a new car will want to know about is its MPG or miles per gallon. In fact, we’d bet that you can accurately name how many MPG your current vehicle gets.

That’s because gasoline is expensive and the lower the MPG, the more you’ll be paying for gasoline for as long as you own the vehicle. However, very few people make this same consideration when shopping for a new HVAC system. But not you! Just by reading this blog, you’re already becoming a smarter consumer.

AFUE: MPG for Furnaces

So how exactly do you measure a furnace’s efficiency? The answer is its AFUE rating which stands for Annual Fuel Utilization Efficiency. The rating reflects how efficiently a gas furnace converts fuel into direct heat energy. 

For example, a gas furnace with a 92% AFUE rating means that it converts 92% of natural gas into heat energy. You may be wondering about the remaining 8%. That 8% is the amount of energy that’s “lost” or wasted. You may be thinking, “That’s not so bad!”

But let’s put these numbers into dollars and cents. A furnace with an AFUE rating of 92% means that for every dollar you spend on gas, 92 cents will go towards heating your home, and 8 cents will be wasted. Now how do you feel about that 92% rating?

Let’s get back to our comparison to MPG. Just like with MPG for a car, a furnace’s AFUE rating indicates how much money you’ll spend on your utility bill for as long as you own the furnace. The higher the AFUE rating, the less you’ll spend on utilities.

Of course, just like with a car, this rating is influenced by other factors. A car’s fuel efficiency rating doesn’t mean much if you neglect oil changes and tune-ups and grossly exceed the speed limit. For a furnace, its efficiency depends on other factors such as your home’s insulation and how you set the thermostat.

The Bottom Line

A high-efficiency furnace will cost less to run but will cost more upfront to purchase. It’s up to homeowners to decide how important efficiency is when it comes to purchasing a new furnace. We’re here to help you make sense of furnace ratings. Contact us for professional advice on choosing a new furnace that’ll meet your initial and long-term budget.

At Covenant Heating and Cooling, we are dedicated to the promise of serving you. Contact us today!

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