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                            Furnace Efficiency Ratings and Why They Matter

So you’ve decided to purchase a new furnace, but you’re unsure about which one to get. You know your current unit needs frequent repairs and the cost is building up. This unit will be heating your home, so it’s important you make the right decision. But which one is right for you? Furnace efficiency ratings can help you determine the best and most efficient heaters for your home.  

Furnace Efficiency Ratings
One of the best ways to determine the quality of a furnace is by looking at their furnace efficiency rating. Every new furnace in the United States is required to show their Annual Fuel Utilization Efficiency rating (AFUE), which is almost always shown as a percentage. The percentage listed on the furnace refers to the amount of heat that’s required to heat your home.

For example, if you see a furnace with an AFUE rating of 80 percent, this means that the furnace uses 80 percent of its fuel and then wastes the other 20 percent. The percentage that isn’t used is usually vented and will be disposed of outside your home. The most common way of disposal is through a chimney, but there can be other ways of ventilation as well.

Some of the best furnaces on the market have an AFUE rating of around 98 percent. Any furnace that has higher than a 90 percent is considered to be a high-efficient furnace. However, the Environmental Protection Agency only requires around a 75 percent AFUE rating for homes.  

So you’ve narrowed down your decision to two furnaces, but you still don’t know which one to get. The Department of Energy (DOE) created an easy way to determine a low, mid and high efficiency for heating systems:


56 percent to 70 percent AFUE.

80 percent to 83 percent AFUE.

90 percent to 98.5 percent AFUE.

Why Do These Matter?
So what’s the big deal with AFUE? Gas is the most common heating system out there. Since a lower AFUE percentage means that your furnace will give off more emissions, environmental concerns may play a role in your final decision. Furnaces that have a higher AFUE rating will almost always cost more because they’re more efficient. For example, a furnace that has a 95 percent AFUE might cost thousands of dollars more than a furnace with a similar size and a lower AFUE rating. However, there are other factors that play a role in the return on your investment. For instance, you might be using your furnace more in harsher climates. Local gas and electricity rates as well as how well your home is insulated will also impact your savings.

Purchasing a furnace is never easy. Let the experts at Cardinal Heating & Cooling help. If you have any questions about AFUE ratings, or you’d like to find out more information about our furnaces, contact us at ed@tuffbird.com