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Making Sense of Furnace AFUE Ratings

When it’s time for furnace replacement in Colorado Springs, the most important thing to take into consideration is its AFUE rating. This measures how energy-efficient a gas furnace is. Let’s use a simple analogy to illustrate just how important an AFUE rating is–and to explain what it means. A furnace’s AFUE rating is similar to a new vehicle’s fuel rating or MPG. 

One of the top things someone who’s shopping for a new car takes into consideration is its MPG. We’d bet that you could tell us exactly how many miles per gallon your current car gets in the city–and on the highway!

MPG is one of the top things to consider because it determines how much you’ll spend on gas for as long as you own the car. And let’s face it–gas is expensive! Anyone who drives a car knows how much gas costs on a day-to-day basis. 

However, not nearly as many people consider fuel and energy costs when purchasing a new furnace. Why is that? It’s just as important because these things influence how much you’ll spend on utilities for as long as you own the furnace.

AFUE Is Like MPG for a Furnace

AFUE stands for Annual Fuel Utilization Efficiency. This rating has one purpose: it tells you how efficiently a gas furnace converts fuel into direct heat energy. 

Here’s an example to illustrate this. A gas furnace with an 80% AFUE rating converts 90% of natural gas into heat energy. The remaining 20% is the amount of energy that’s wasted. You might be thinking that’s not much of a loss. 

But it’s when you consider these numbers as dollars and cents that you begin to see how much of a loss it is. A furnace with an 80% AFUE means that for every dollar you spend on gas, 80 cents will go towards heating your home, and 20 cents will be wasted. That’s quite a lot! Imagine spending $75 to fill up your car’s gas tank and only getting $60 worth of gas. 

The higher the AFUE rating, the more energy-efficient the gas furnace will be. That means the higher it is, the less you’ll spend on utilities. With furnaces having AFUE ratings as high as 98%, you can now see what a difference there is between the minimum AFUE rating of 80% and the most energy-efficient furnaces on the market.

However, just like with a car, energy efficiency is influenced by other factors. How many MPG a car gets doesn’t matter that much if you skip tune-ups and drive 90 MPH on the highway. 

With a furnace, its energy efficiency depends on things such as whether you get maintenance every year, changing the air filter regularly, how well your home is insulated, and how high you set the thermostat.

We’re here to help you choose the furnace that’s best for your budget and your home. 

Don’t let the weather get you down, call Brown’s! Brown’s Heating & Cooling is your trusted resource for furnace replacement in Colorado Springs. Contact us today!

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