What is SEER rating?
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SEER stands for Seasonal Energy Efficiency Ratio. It measures the energy efficiency of your air conditioner.
With new AC efficiency standards on the horizon in 2023, SEER may be on your mind if you’re purchasing a new air conditioner or building a new home.
Shopping for a new air conditioner?
What does SEER rating mean?
The U.S. Department of Energy joined forces with the Air Conditioning, Heating, & Refrigeration Institute to create the SEER measurement. The industry group includes more than 300 air conditioner manufacturers across North America.
The SEER rating quantifies overall AC system efficiency on a seasonal basis. It helps consumers compare energy efficiency when choosing a new air conditioner.
How is SEER rating calculated?
To calculate an AC’s SEER rating, divide its cooling output by its electric energy input during a typical cooling season. The higher the number, the more efficient the AC.

For example, if an AC puts out 5,000,000 BTU of cooling seasonally while using 300,000 kW of electricity, its SEER is 16.6 (5,000,000/300,000 = 16.6).
SEER testing occurs in a laboratory setting that simulates indoor and outdoor environments. Generally, the outdoor temperature is just two degrees higher than the indoor temperature in the simulation.
The laboratory controls the conditions for consistent and accurate results. However, they don’t necessarily reflect reality. For example, your AC may consume more electricity in your home compared to the laboratory.
SEER vs. EER
One distinction to be made is SEER vs. EER. The “S” refers to the average operating time and energy efficiency over the entire summer season.
Comparatively, EER is only a snapshot of the efficiency of a system at one moment in time based on specific conditions.
What is a good SEER rating?
In the northern United States, new HVAC systems must have a minimum SEER of 13. In the South and Southwest, 14 is the minimum SEER. Come 2023, these minimums will change to 14 and 15, respectively.
Older ACs have lower SEER ratings in most cases. For example, air conditioners from the 1990s are generally rated 8-11.
SEER ratings of 13-15 are considered good, 16-19 are better, and 20-24 is best.
SEER chart

The highest-SEER central AC currently available is rated 26. This is far more energy-efficient than most models on the market today. Carrier, Bryant, and Lennox make 26-SEER air conditioners.
Mini splits are typically more energy efficient than even the best central ACs. Carrier makes the highest-SEER mini split with a rating of 42. Again, this rating is impressive but atypical.
Schedule a consultation with a local air conditioning expert.
Is a high SEER worth it?
The higher the SEER, the more efficient the air conditioner. This is good news for the environment and your savings account. However, higher-SEER ACs are usually more expensive upfront.
Higher-SEER air conditioners have several notable advantages:
💧 Less humidity | High-efficiency systems more effectively remove moisture from indoor air. This may mitigate mold issues and other airborne contaminants. |
🌎 Better for the environment | Energy-efficient air conditioners release fewer greenhouse gasses and burn less fossil fuel. |
💰 Incentives and rebates | You may find rebates on state and national levels for energy-efficient HVAC equipment. The ENERGY STAR site is a great place to start looking. |
💵 Lower utility bills | Less energy consumption leads to lower power bills. See what you can expect to save using this helpful calculator. |
The rebates and cost savings you experience with a higher-SEER AC cancel out the higher price in just a few years. Purchasing the highest-SEER system you can afford is a smart investment if it’s time to replace your air conditioner.
If you’re interested in learning more, check out this article, where we examine the pros and cons of purchasing a 14-SEER vs. 16-SEER air conditioner.
What is SEER 2?
The SEER 2 standard will replace the SEER rating in 2023. The main difference is the testing conditions.
SEER 2 requires a higher external static pressure during testing. This change makes the laboratory conditions more like a real-world ducted AC system.
The SEER formula remains the same with SEER 2. However, most systems will likely receive a slightly lower rating in the new testing conditions. For example, an air conditioner rated 16 with SEER may earn a 15.4 with SEER 2.
Starting in 2023, all air conditioners for sale must list their SEER 2 rating.
The bottom line on SEER
We believe it’s wise to splurge on the highest-SEER system within your budget. Not only will you save money in the long run, but you’ll also positively impact the environment.
If your AC is currently running fine, there’s no need to dump it and buy a higher-SEER system. But when the time comes for a replacement, go big on SEER.
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