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EER2: Energy Efficiency Ratio — What is a Good EER2 Rating for AC?

EER, or Energy Efficiency Ratio, measures the energy efficiency of an air conditioner or heat pump at the outdoor cooling temperature of 95°F. EER2 is an updated version of EER that all cooling systems need to abide by starting Jan. 1, 2023.

A higher EER2 rating means your air conditioner is more energy efficient — and that’s a good thing! An energy-efficient AC will save you money on your utility bills and leave a small carbon footprint in the process.

What is EER2?

Like we mentioned earlier, EER2 is the energy efficiency of your air conditioner or other cooling system. EER2 ratings are always calculated with the unit working at an outdoor temperature of 95°F, an indoor temperature of 80°F, and at 50% humidity.

What’s a good EER2 rating for an air conditioner?

The Department of Energy has set minimum EER2 standards that all air conditioners must meet starting Jan. 1, 2023. Minimum standards vary based on region of the country and system capacity, so be sure to talk to your local independent Trane dealer to find out what rating works best for you and your home.

EER2 vs. SEER2

EER2 and SEER2 both evaluate an air conditioner’s energy efficiency, but they’re concerned with two different types of temperature conditions:

  • EER2 measures an air conditioner’s efficiency at the peak cooling temperature of 95°F.
  • SEER2, or Seasonal Energy Efficiency Rating, measures an air conditioner’s efficiency throughout an entire cooling season, with temperatures ranging from 65°F to 104°F.

Think about SEER2 as being an average of AC efficiency, while EER2 is one specific data point. You can expect Trane’s product descriptions to include SEER2 rather than EER2, because EER2 reflects specific conditions, so it may not apply to some homeowners. SEER2 is more widely applicable and is often more meaningful than EER2 to a larger group of AC owners.

As of Jan. 1, 2023, minimum SEER2 ratings for single-packaged air conditioners throughout the region and split system air conditioners in the North must be 13.4 or higher. In the Southeast and Southwest, split system air conditioners with a capacity less than 45k BTU must have a SEER2 of 14.3 or higher. Split system air conditioners with a capacity greater than or equal to 45k BTU must have a SEER2 of 13.8 or higher.

When does understanding EER2 matter?

While understanding EER2 is important for all AC unit owners to get the full picture of their unit’s efficiency, understanding EER2 is especially important if you live in the Southern United States or a state like Arizona or Florida, where high, humid temperatures are the norm.

EER2 ratings are typically more important for those living in the Southern U.S. because EER2 is calculated by using one temperature — 95°F. In the South, it’s pretty standard for summer days to reach and exceed this high temperature, so EER2 is crucial in understanding how your air conditioner will hold up during hot days. In the North, such high temperatures aren’t as common, so a rating of how energy efficient your AC unit is at this high degree isn’t going to be too useful for you.

If a unit has a really high SEER2, but a really poor EER2, it means it’s really efficient in mild and cool conditions, but has poor efficiency when it’s really hot. This is very important for homeowners who live in extreme temperatures to understand, so you can get a unit that best suits your lifestyle!

Need Help?

A high EER2 rated air conditioner could save you money on your utility bills and help the environment in the process. If you’re looking to purchase or upgrade a room air conditioner, a Trane Comfort Specialist™ can help.

Contact a local dealer

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