How To Look At A House

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What is the SEER of my old air conditioner?

Saturday, July 28, 2018

The chart below traces the history of the average SEER (Seasonal Energy Efficiency Rating) for residential air conditioners dating back to the 1980s. During each era there were also “high efficiency” models, often proudly announced by a fancy medallion on the condenser unit, so some older systems may exceed these numbers. The manufacturer’s nameplate will also give you a clue, with “XE900” indicating a 9 SEER system, for example.   As the SEER number increases, the energy usage for the same amount of cooling decreases proportionately. This means that a 12 SEER unit will cool your home using half the energy of a 6 SEER, and a new 13 SEER system is about 30% more efficient than a 10 SEER from the early 1990s. 

   Mandates by the U.S. Department of Energy have pushed minimum SEER ratings upward every decade or so. Air conditioning units manufactured in1992 and later were required to have a minimum 10 SEER, and the minimum was reset again to 13 SEER in 2006. It was reset again at 14 SEER in 2015, and scheduled to go up to 15 2023. Today manufacturers offer higher SEER models for 20% or more above base model prices for minimum SEER unit, and up to 20 SEER and higher is also available.

   While the chart above outlines average SEER ratings for each era of air conditioning production, if you want to know the exact SEER of your air conditioning system, go to our blog “How can I find out the SEER of my air conditioner?”

    Also, see our blog posts How can I find out the size of my air conditioner? and How can I find out the age of my air conditioner or furnace?

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

• Why does it say INSTALLATION PROHIBITED IN THE SOUTHWEST on my air conditioner label?

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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