Upgrading to energy-saving equipment is one of the most effective ways to counter rising heating costs. With so many choices on the market, understanding furnace efficiency ratings is a critical tool in selecting the right system for your Grayslake, IL home.
Calculating Furnace Efficiency Ratings
The AFUE (Annual Fuel Utilization Efficiency) rating is calculated based on how much fuel a furnace consumes while producing heat compared to the amount of energy burned up by ventilating noxious gases. An AFUE rating of 95%, which is common among modern gas-powered furnaces, means only 5% of the energy is lost. The ratio measures the average yearlong efficiency of how the equipment utilizes its fuel source rather than a precise daily output.
Higher Ratings Equal Less Energy
Furnaces with higher ratings use less energy to heat your home, which translates into bigger savings on utility costs. Based on an 85% AFUE, for every $1 spent, 15 cents does not go toward heating your home. Since electric furnaces have no flue loss, AFUE ratings range between 95% and 100%. Units installed outside have lower scores because of greater jacket heat loss. Due to varying components, gas furnaces have furnace efficiency ratings spanning 55% to 97%.
Factors Affecting Furnace Efficiency Ratings
According to the Department of Energy, factors that contribute to lower ratings between 56% and 70% include a continuous pilot light and heavy heat exchanger. Older systems also have a natural draft that increases the flow of combustion gases. Mid-efficiency furnaces utilize an exhaust fan to more precisely control the flow. An electronic ignition, compact size, and smaller flue result in an AFUE of 80% to 83%. By condensing the flue gases in a second heat exchanger and operating sealed combustion technology, furnaces can achieve a 90% to 95.5% AFUE.
Federal Trade Commission regulations require every new furnace to display its AFUE rating. Contact our Carrier-trained HVAC technicians at (847) 260-9335 to discuss your new furnace questions or to learn how Herchenbach Mechanical can assist with a heating system replacement.
