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Carney All Seasons Blog

How to Judge the Efficiency of Your Heating System

No one likes to deal with needing to replace their heating system right at the beginning of winter, but if it has to happen, it has to happen. Replacing an outdated or failing heater provides you with the opportunity to explore using a different kind of heating system, as well as improve your home’s comfort and efficiency. How do you know how efficient a certain heater will be? You need to look at its rating.

Two Kinds of Ratings

When it comes to heating systems, there are two types of ratings: AFUE and HSPF. AFUE stands for annual fuel utilization efficiency and is the rating found on furnaces and boilers. The HSPF rating stands for heating seasonal performance factor and is the rating system for heat pumps. Understanding how these two ratings work and what they mean in the context of efficiency will help you determine which heater will be best suited to replace your existing one.

How AFUE Works

The AFUE rating is expressed as a percentage. The minimum AFUE you will find is 78% because that is the standard by which all furnaces and boilers must meet. But on a scale that reaches 100%, 78% isn’t all that great. The good news is that you can choose a heater with a much higher AFUE rating, but be aware that the higher the rating, the more costly the purchase price.

AFUE tells you how much fuel is utilized for energy and how much is lost to combustion byproducts. A furnace with an AFUE of 89% tells you that most of the fuel used creates heat for your home, but that 11% of your total fuel will be lost as combustion byproducts.

How HSPF Works

HSPF works a little differently because heat pumps don’t consume a fuel to operate. Instead, they transfer heat from one location to another using refrigerant. The HSPF scale runs from 7.7, which is the mandated federal minimum, to 10.0, which is the highest efficiency rating for a heat pump system. The HSPF rating tells you is the number of BTUs (British thermal units) of heat a particular heat pump system moves for every watt-hour of electrical energy used.

Need help discerning this information for your heating installation or replacement in Newtown, PA? Call the pros at Carney Plumbing Heating & Cooling today!

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