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How AFUE Ratings Affect Your New Heater

If you’ve looked at the cabinet of a furnace or a boiler, you may have noticed something called the “AFUE rating.” This is one of the most important stats to know about the new heating system you decide to install, because it will have an effect on your heating bills for many years to come… as many years as you the heating system lasts. We’ll explain what AFUE means and how it affects your new heating system.

Make sure that you don’t purchase a new heater without help from professionals. Design Comfort installs many types of systems and provides heating repair service in Salt Lake City that will keep any heater humming away.

AFUE rating and what it means for you and your heater

AFUE is a way of rating the efficiency of heating systems like furnaces and boilers. (Heat pumps have a separate dual rating, SEER/HSPF.) The initials stand for “annual fuel utilization efficiency,” and is expressed as a percentage. The percentage represents how much of the heater’s fuel supply it changes into heat. For example, a gas furnace with 78% AFUE produces 78 BTUs of heat for every 100 units of gas available. This means it produces a waste of 22 units of fuel, which goes unburned. The higher the percentage, the more completely the heater consumes fuel and turns it into heat power.

For a gas furnace to earn the EPA’s ENERGY STAR label for efficiency in Utah, it must have 95% AFUE or greater. All furnaces produced in the U.S. must have at least 78% AFUE. For boilers to receive the ENERGY STAR label, they must have 85% AFUE or higher.

A furnace’s AFUE rating isn’t a guarantee of heating effectiveness. You may not get the level of comfort you desire from a high-AFUE furnace or boiler, especially if it was installed poorly or sized incorrectly for your home. However, a high AFUE rating does mean lower energy bills. For example, if you changed from an old 70% AFUE furnace to a new model of 90% AFUE, for every 1000 BTUs you burned, you would save $136. The savings with higher efficiency furnaces and boilers can be substantial.

However, higher AFUE models are usually more expensive. When it comes to picking a new furnace or boiler, you’ll have to weigh upfront costs against long-term budget plans. In most cases, you can expect larger savings from a higher AFUE model. But you should consult with an installation professional to help you make the best choice possible.

Design Comfort has a staff with NATE-certified technicians with many years of experience installing heaters and providing heating repair in Salt Lake City, UT. They can assist you with picking a heater with the AFUE rating that will work for you and keep you warm for many years.

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