Figuring Out How Efficient Your Furnace Should Be

The efficiency of your new furnace requires going beyond its Annual Fuel Utilization Efficiency (AFUE) rating, which computes the percentage of fuel consumption that actually contributes to heating your home, versus that which is lost in the combustion process. Federal law requires new units sold today to have an AFUE of at least 78, and the ratings on high-efficiency condensing models now range as high as 97. However, no single metric tells the entire story of how much energy you’ll use, nor what your potential savings in operating costs will be. Your HVAC contractor will take these other factors into consideration when suggesting a furnace that provides the optimum balance of performance and efficiency:

• How efficient your furnace needs to be is directly related to the general efficiency of your home. An experienced professional will consider factors such as air-tightness of the structure, condition of ductwork and the amount of installed insulation.
• AFUE only calculates the efficiency of gas consumption. However, all gas furnaces also use electricity to run the blower fan and this factor may contribute significantly to overall operating cost. Variable-speed electronically commutated motor (ECM) blowers available as an option on most new units consume less electricity than conventional permanent split capacitor (PSC) motors that are often standard equipment.
• Generally speaking, the greater the efficiency, the higher the upfront purchase price. Whether a more expensive, high-efficiency unit will pay back that price differential in lower operating costs over it’s expected service life, however, depends greatly on the local climate and the length of the average heating season.

A qualified HVAC contractor doesn’t use guesswork to determine how efficient your furnace needs to be. He’ll quantify the factors above, assess other variables such as installation costs and local utility rates, then enter the data into industry-standard software that enables him to suggest a choice of models in a range of efficiencies and purchase prices that are appropriate matches to your home and budget.

For more details about determining optimum furnace efficiency, contact the professionals at C.R. Wolfe Heating in Middletown.

Our goal is to help educate our customers in Middletown, New York about energy and home comfort issues (specific to HVAC systems).  For more information about Furnaces and other HVAC topics, download our free Home Comfort Resource guide.

Image courtesy of Shutterstock