Gas Furnace Efficiency Calculator

With a less efficient furnace operating at 80 percent efficiency this would require a 60 000 to 72 000 btu furnace.

Gas furnace efficiency calculator.

Lennox gas and oil furnaces are engineered to deliver perfect warmth efficiency and energy savings. Using an online calculator and considering average gas prices in the us the results for a 1800 sq. Delivering precise comfort and temperature control lennox furnaces can keep your home to within 0 5 degrees of your ideal temperature. As quiet as they are efficient lennox furnaces also startup and run perfectly quietly helping to preserve the peace and quiet of your home.

With a high efficiency furnace operating at 95 percent the home only needs a. The only time you can rely on afue as a sole comparison is when comparing two furnaces with the same fuel type. Thus efficiency alone is not an indicator of operating costs. For example if a furnace has a listed input rating of 90 000 btu s and an efficiency rating of 80 it will produce 90 000 btu input x 80 efficiency 72 000 btu actual output.

Furnace information estimated efficiency of present furnace. Then to calculate the output on a given gas furnace multiply it s efficiency rating by it s listed input rating to determine the actual btu output of heat. For this comparison exercise we will assume a 65 afue furnace is getting replaced by a standard efficiency 80 or a high efficiency 95 furnace.