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What Is the AFUE of a Furnace?

Before buying a furnace, there are several factors to consider for the Sewell, NJ homeowner. Beyond the price, fuel source, and maintenance expectations, it is just as essential to consider the AFUE.

But what is the AFUE? How do you determine the AFUE? Not to worry, because this guide will explain everything you need to know about AFUE ratings.

What Is an AFUE Rating?

An AFUE rating is a calculation used to determine energy efficiency. It stands for Annual Fuel Utilization Efficiency, and it can tell you how useful a furnace is at producing heat every year.

For instance, a furnace with an AFUE of 80 will convert about 80% of its fuel into usable heat, while about 20% will waste through air leaks, poorly designed burners, or a less sophisticated design. In contrast, a furnace with an AFUE of 95 will turn 95% of its fuel into usable heat.

The US Environmental Protection Agency (EPA) mandates all heating systems except those used in mobile homes be rated at least 75%. Mobile homes are only required to have a 75% efficiency rating.

Understanding AFUE Rating for the Homeowner

While shopping for a brand-new furnace to install in your Sewell, NJ home, consider a furnace’s Annual Fuel Utilization Efficiency rating to gauge its efficiency. Today’s most efficient furnaces have an AFUE of about 98.5%.

The American standard mandates that new gas furnaces have an AFUE of 78%. A mid-efficiency unit has an AFUE rating of 80 to 83 percent per the EPA. On the other hand, high-efficiency units have a rating of 90-97 percent.

In the past, heating units were not legally required to offer the same AFUE levels mandated today. So, if you have an older furnace, the AFUE rating may significantly impact your heating cost.

The Department of Energy first set AFUE ratios for heating equipment in 1975, when they issued guidelines governing minimum efficiency. In 1987, 78% became the minimum fuel utilization efficiency. However, it rose to 80% in 2015.

Every year, the efficiency of furnaces decreases, so it is possible to have a furnace with a high AFUE rating but still be inefficient. If your furnace meets the new AFUE standard, but your monthly heating costs are not decreasing, a furnace repair in Sewell, NJ, may be in order.

Standard Features of Furnaces with High AFUE

The following are fundamental features of high-efficiency furnaces:

  • A secondary heat exchanger that can harness more heat energy for air heating
  • Energy-saving blowers with variable speeds that can distribute air at higher or lower speeds
  • The furnace can produce different amounts of heat depending on the needs of the household, with a variable heat output
  • For better efficiency, hot surface ignition replaces the pilot lights in older furnaces
  • Better filtration systems improve the home’s air quality.

Contact Our Team Today!

Are you considering buying a new furnace? Do you need a furnace repair? Either way, our team at SPS Mechanical Inc. is here for you! Give us a call or fill out our online contact form to schedule a free, no-obligation estimate. Comfort At Your Service.

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