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AFUE is the Key Word When Shopping for Furnaces in this Cold Climate


The Annual Fuel Utilization Efficiency (AFUE) rating tells you how much value you get for every dollar spent on heating. Basically if you paid X dollars for oil or gas towards heating of your rooms, AFUE will tell you what fraction of the amount showed up in your rooms as heat. So, if your AFUE rating is 80%, then it means that for every $100 spent on heating, you only get $80 worth of heat in your rooms. The other $20 goes out through the chimney or is lost in other ways. Each heating furnace or boiler is assigned an AFUE number.

AFUE is not the be all end all of heating efficiency

While EFUE helps you determine the efficiency of a heating system, the metric should never be used alone in establishing the efficiency of a heating system. Lab reports from the U.S. Department of Energy indicate that AFUE is inaccurate, particularly for boilers that make water hot.

The Department of Energy’s Brookhaven National Laboratory, for instance, confirms that AFUE misses significant areas when it comes to energy loss. According to a study released by the Laboratory earlier on, AFUE ratings could be off by up to 25 percent. Such an error can underestimate your fuel consumption efficiency by as much as 47 percent.

You still need regular maintenance

A high-performance heating system that isn’t properly maintained will still operate inefficiently. You need to clean and service the heating system regularly to improve efficiency.

Actually, a heating system rated at 90 percent by AFUE might run at lower than 80 percent efficiency if not maintained properly. Get in touch with our AC Repair in Euless TX specialists for more info.

It is also important to properly insulate the building in order to achieve greater heating efficiency. For your ultimate guide and AC Repair in Euless TX, contact our team of specialists.

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