SEER2 Rating: Calculator, Requirements and Chart

SEER2, or Seasonal Energy Efficiency Ratio 2, measures the cooling efficiency of air conditioners and heat pumps.

How is SEER2 Different from SEER?

SEER2 is the latest SEER rating for measuring how much energy a cooling system needs to produce a certain amount of cooling. Original SEER testing encountered larger discrepancies between laboratory test results and actual operational tests, with SEER rating using a static external pressure calculation value of 0.1 inches of water column (inch wc). With SEER2, external static pressure has now been changed to 0.5 inches of water column (inch wc), a more realistic value for most homes.

M1 blower door testing procedure results have also been introduced to more accurately represent real-world conditions. The new appendix M1 testing procedure uses the same variables, but with new efficiency metrics; SEER2, EER2, and HSPF2, all based on current efficiency factors, but with changes to the calculation’s numerical values. The new SEER2 testing and rating system aims to provide a more accurate forecast of total heat removed, and total electrical energy consumed during an annual cooling season. Testing standards are being introduced by the US Department Of Energy (DOE) and will be in effect from January 1, 2023 onward.

How Is SEER2 Calculated?

The SEER formula itself hasn’t changed with SEER2 calculations, as you can see below:

The seasonal energy efficiency ratio formula is simple: divide the cooling output for a typical cooling season by the total electric energy input for the same time period. A higher ratio between cooling output and total electric energy input represents a higher cooling season energy efficiency.

What are the SEER2 Minimum Requirements?

SEER2 Requirements vary based on region. Three regions currently stand: North, Southeast, and Southwest United States. The traditional SEER rating, for all regions, will have its minimum requirement increase by approximately 1 SEER to be on par with the new SEER2 requirements. The North region‘s SEER rating will increase from 13 to 14, while the Southeast and Southwest will increase from 14 to 15 SEER. Heat pumps (HPs) in any region must meet the minimum SEER rating requirement of 15 SEER (Now 14 SEER2) and 8.8 HSPF (7.5 HSPF2). 

A table of residential central AC and split system SEER2 ratings per region can be found below:

In both the southeast and southwest regions, any AC that doesn’t meet the SEER2 requirements cannot be installed on or after January 1, 2023.

North Region Minimum Requirements

SEER2 compliance for systems in the north region is based on each HVAC system’s manufactured date. In the north region, any 13.0 SEER AC unit built before January 1, 2023, can still be installed on or after January 1, 2023. In the north region, for installers and designers, compliance is determined by the system’s manufacturing date. 

For the north region to meet SEER2 requirements:

• Residential central air systems below 45,000 BTU must have a SEER2 of 13.4 (14.0 SEER).
• Residential central air systems 45,000 BTU and above must have 13.4 SEER2 (or 14.0 SEER) as well. 
• Any 13.0 SEER air conditioner built before January 1, 2023 can still be installed on or after January 1, 2023, allowing ample time to sell all 13 SEER existing inventory. 13 SEER air conditioners made on or after January 1st must adhere to the new SEER2 standard.
• Heat pumps in the north region must meet at least 14.0 SEER2 (15 SEER) and 7.5 HSPF2 (8.8 HSPF) requirements. 14 SEER heat pumps are still allowed in the north region if your system was manufactured before January 1, 2023, and is considered “existing inventory”.
• Current SEER ratings of a single packaged unit are 14.0 SEER and 8.0 HSPF. This will remain the same despite other regulatory changes. However, these units will still need to adhere to the new testing measures and meet SEER2 rating requirements of 13.4 SEER2 and 6.7 HSPF2.

Southeast

For the southeast region to meet SEER2 requirements:

• Residential central air systems below 45,000 BTU must have a rating of 14.3 SEER2 (15.0).
• Residential central air systems 45,000 BTU and above must have a rating of 13.8 SEER2 (14.5 SEER).
• All air conditioning systems purchased in the southeast region that do not meet the SEER2 requirements cannot be installed after January 1, 2023.
• Existing 14.0 SEER heat pumps built prior to January 1, 2023 can still be sold on or after January 1, 2023. Heat pumps in the southeast region must meet 14.3 SEER2 (15.0 SEER) and 7.5 HSPF2 (8.8 HSPF) requirements.
• Current SEER ratings of single packaged units are 14.0 SEER and 8.0 HSPF, this will remain the same despite other regulatory changes. However, these units will still need to adhere to new testing standards and meet the new ratings of 13.0 SEER2 and 6.7 HSPF2.

Southwest

All air conditioning systems purchased in the southwest region that do not meet the SEER2 requirements cannot be installed after January 1, 2023.

*Lower EER2 requirements for equipment already equal to or greater than 15.2 SEER2.

For the southwest region to meet SEER2 requirements:

• Heat pumps in the southwestern region must meet 14.3 SEER2 (15.0 SEER) and 7.5 HSPF2 (8.8 HSPF) requirements.  Existing 14.0 SEER heat pumps built prior to January 1, 2023 can still be sold on or after January 1, 2023.
• For gas, electric, splits, and packaged AC systems – Southwest SEER2 compliance is based on date of installation.
• Residential central air systems below 45,000 BTU must have a SEER2 rating of 14.3 SEER2 (15.0 SEER).
• Residential central air systems 45,000 BTU and above must have a SEER2 rating of 13.8 SEER2 (14.5 SEER).

Below is a table of minimum SEER2 rating for air conditioners by state:

What Are the Benefits of a Higher SEER2 Rating?

A higher SEER2 Rating can greatly enhance your home’s interior atmosphere. In summer, mostly in hotter climates like the Southeast or Southwest, you will be more comfortable while enjoying reduced electrical costs. Once full SEER2 compliance is achieved, national energy consumption is expected to be reduced by 5% or more. 7% savings or greater is expected, depending on the SEER2 rating of the unit. 

What Is the Difference Between SEER2 Rating and EER2?

SEER2 is a measurement of a system’s energy efficiency ratio over the course of an entire season, providing a rounded number. EER2 measures a system’s energy efficiency during high load, or during the hottest time of the year. Both SEER2 and EER2 measure a system’s cooling efficiency.

What Is the Difference Between SEER2 Rating and HSPF2?

Seasonal Energy Efficiency Ratio 2 (SEER2) is a measure of a system’s cooling efficiency. Heating Seasonal Performance Factor (HSPF2) measures a system’s heating efficiency. New static pressure values and M1 building blower tests have been added to both SEER2 and HSPF2. Both ratings have minimum values based on region, and now vary based on regional requirements. 

How Do You Find the SEER2 Rating on an AC?

Every air conditioner has a SEER rating listed within its specifications. On units prior to January 1, 2023, contact to the manufacturer using serial number and model number may be necessary to determine a system’s SEER rating. Manufacturers are now printing the SEER2 on the machine’s technical data tag, normally found on the condenser unit.

Source: US Energy Information Administration

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Jim Dorsey

Writer and Reviewer at HeatingandCoolingUSA

Jim has 40 years of experience working in the residential and commercial HVAC Industry. He is certified in Environmental Control 1, Environmental Control 2, and Environmental Control 3- HVAC Heating and Industrial Electrical Service Certifications from the Society of Building Science Educators (SBSE) and holds a universal Refrigerant Training and Certification EPA card.

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