What does the SEER rating of an air conditioner mean?

Saturday, October 6, 2018

It’s an acronym for Seasonal Energy Efficiency Ratio, and expressed as a number that typically ranges between 10 and 20; which is a ratio of the cooling output during a typical cooling-season divided by the electric energy input during the same period. Because it is a ratio, there is no unit of measure after the number; however, it could also be termed as BTU’s per watt/hour. 

   It is comparable to the miles-per-gallon rating for a car and, essentially, a higher SEER rating means better energy efficiency. A yellow sticker on the condenser (outside part of a/c system) is affixed at the factory stating the SEER rating of the unit. Starting in 2006, the federal government required that new residential air conditioning systems have a minimum SEER of 13. Pre-2006 systems had SEER ratings mostly between 8 and 12, with the older units being the least efficient. The current minimum SEER is 14.

    A minimum SEER of 14.5 is required to garner an “ENERGY STAR” rating, and possibly qualify for a tax credit or rebate from your local utility. Window a/c units, at the other end of the spectrum, are exempt from the mandate, so their efficiency still hovers around 10. 

    Also see our blog post How can I find out the SEER of my air conditioner?  For advice on when to replace an older system, see our blog post Is it cost-effective to replace an older, low-efficiency air conditioner system with a new high-SEER system?

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  To learn more about heating and air conditioning systems, see these other blog posts:

How can I find out the SEER of my air conditioner? 

My air conditioner won't turn on. What's wrong? 

How can I find out the size of my air conditioner? 

How can I tell whether the condenser (outdoor unit) is an air conditioner or heat pump? 

Where is the air filter for my central air conditioner and furnace? I can’t find it? 

Does an old air conditioner use more electricity as it ages? 

How did homes stay cool in Florida before air conditioning? 

What is wrong with an air conditioner when the air flow out of the vents is low?

Why has the thermostat screen gone blank? 

Why does it take so long to cool a house when an air conditioner has been off for a while? 

Why is my air conditioner not cooling enough? 

What are the most common problems with wall/window air conditioners?  

Will closing doors reduce my heating and cooling costs? 

   Visit our HEATING AND AIR CONDITIONING page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles. 

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