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Questions We Often Hear About Furnace Efficiency

question-mark-badgeEnergy efficiency. It’s a big concern people have about appliances today. It isn’t enough for an appliance to work, it should also work without unnecessarily draining power. Modern manufacturers know how important this is to customers and make their products to match, and the U.S. Department of Energy has put in place the ENERGY STAR program to test and mark products that conserve power.

The efficiency question is a vital one for furnaces because they are essential appliances for home comfort and because they consume a large amount of energy each winter. An electric iron with the ENERGY STAR label may save a few cents. A high-efficiency furnace can potentially save hundreds of dollars.

Because we know that you are probably interested in furnace efficiency, we’re going to answer some of the questions we often get from customers about it.

How is furnace energy efficiency measured?

The measurement is Annual Fuel Utilization Efficiency, or AFUE. It’s a percentage that tells how much of the furnace’s fuel source—such as natural gas—is converted into heating power. The higher the percentage, the more efficiently fuel is burned. A furnace with an 80% AFUE rating turns 80% of the natural gas it burns into heat, and 20% goes to waste.

What’s considered a high AFUE rating?

For a gas furnace to receive the ENERGY STAR label in New Jersey, it must have an AFUE of 95% or higher.

Electric furnaces have an AFUE of 100%. Does that mean they’re better?

This is where it’s important to distinguish between efficiency and energy cost. An electric furnace has 100% AFUE because no energy from the electricity is lost to exhaust gases like in a natural gas or oil furnace. However, electricity is more expensive an energy source—so you can expect to pay more to run an electric furnace than a gas furnace.

How do high-efficiency furnaces manage to be so efficient?

There are a number of different technological advances that allow for improved efficiency. When a furnace has an AFUE rating of higher than 95%, it’s probably because it’s a condensing furnace. This means the furnace takes the exhaust gases from the heat exchanger and moves it to a second heat exchanger, where it’s condensed to release even more heat. Other innovations that improve efficiency are variable speed fans, sealed combustion chambers, and multi-stage burners.

Do high-efficiency furnaces offer other benefits aside from lower costs?

It depends on the features. Variable speed fans and multi-stage burners allow for more even distribution of heating—a house is much less likely to become stuffy during the winter. Sealed combustion furnaces help prevent the air indoors from becoming too dry in winter.

Is a high-efficiency furnace worth the cost?

Another “it depends” answer. If a new furnace is properly installed, it will operate at a lower cost than a furnace with lower AFUE. But the more efficient a furnace, the more expensive it is to purchase, and the longer the payback period (rate of return). If you plan to stay in your home for 10 years or more, a high-efficiency furnace is a good investment.

We provide furnace services in Cranford, NJ: installations, replacements, repairs, maintenance. We can help you make the best choice for a new furnace installation.

Air Creations, Inc. serves Central and Northern New Jersey. “We Do It Right!” since 1987.

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