1. Introduction: New HVAC Efficiency Ratings Effective 2023
Starting January 1, 2023, the U.S. Department of Energy (DOE) introduced a new way to measure air-conditioner and heat-pump efficiency.
These updates replaced the long-used SEER, EER, and HSPF ratings with SEER2, EER2, and HSPF2 and also increased the efficiency standards.
The goal? To better reflect real-world performance rather than idealized laboratory conditions.
Every single-phase air conditioner and heat pump below 65,000 Btu/hr is now rated using these new standards — and these numbers also affect Title 24 Energy Code compliance in California.
2. What Do SEER, EER, and HSPF Mean?
Before jumping into SEER2 and HSPF2, let’s recap the original metrics:
- SEER (Seasonal Energy Efficiency Ratio) – Measures how efficiently a cooling system operates over an average cooling season. Higher SEER = lower energy use to cool the home.
- EER (Energy Efficiency Ratio) – Evaluates efficiency at a fixed outdoor temperature (usually 95°F).
- HSPF (Heating Seasonal Performance Factor) – Applies to heat pumps; measures seasonal heating efficiency.
These labels have been used for decades on HVAC equipment, design plans, and compliance forms.
3. Why the DOE Introduced SEER2, EER2, and HSPF2
The DOE’s updated test procedure was designed to simulate real-world operating conditions more accurately.
Under SEER2 testing, systems are evaluated with higher external static pressure, accounting for duct losses and installation factors that were often ignored before.
In practice:
- SEER2 values are typically about 4–5 percent lower than their old SEER equivalents.
- EER2 and HSPF2 show similar downward adjustments.
- The ratings themselves are not worse—they’re simply more realistic.
These new metrics apply to all newly manufactured central air conditioners and heat pumps after January 1, 2023.
4. How the Change Affects California Title 24 Energy Code
California’s Energy Commission (CEC) has provided clear guidance on handling this transition.
- For projects submitted under the 2019 Energy Code, equipment may still be listed with old SEER values on the CF1R (Title 24 Certificate of Compliance).
However, the equipment installed today will only carry SEER2 ratings. - To bridge the gap, CEC has released an official conversion table that allows you to convert SEER2 → SEER (and likewise for EER and HSPF) when completing the CF2R (Certificate of Installation). We created the below helpful calculator in section 5 to help convert these values.
- The new DOE testing procedures and efficiency rating updates also affect the minimum HVAC efficiency requirements that apply in California. These updated values are listed in Section 6 below.
👉 View the official CEC Blueprint with conversion guidance here.
For all projects permitted under the 2022 Energy Code, you must use SEER2/EER2/HSPF2 values directly — no conversion required.
5. SEER2 ↔ SEER Conversion Tool
Quickly Convert SEER2, EER2, and HSPF2 Values
Use the tool below to calculate equivalent SEER, EER, and HSPF ratings for your HVAC equipment per the formulae provided by the California Energy Commission. This is helpful for projects still permitted under the 2019 Energy Code, where older SEER-based values appear on compliance documents. This is applicable only for California.
How to Use the Calculator
- Select which rating you’d like to convert (SEER2, EER2, or HSPF2).
- Enter your equipment’s value (for example, SEER2 = 15.0).
- View the approximate converted SEER/EER/HSPF value instantly.
- Use this converted value on CF1R or CF2R documentation while noting the actual SEER2 rating in your project notes.
Important Notes
⚠️ These conversions are meant for California Title 24 documentation on the 2019 Title 24 code only.
Always verify official equipment efficiency ratings from the manufacturer or CEC appliance database.
6. Updated Minimum Efficiency Requirements for California (Southwest Region)
As of January 1, 2023, the U.S. Department of Energy (DOE) has updated the minimum efficiency standards for air conditioners and heat pumps in the Southwest region, which includes California.
The updated minimum ratings are:
- Split Air Conditioners (< 45,000 Btu/h): 14.3 SEER2, 11.7 EER2
- Split Air Conditioners (≥ 45,000 Btu/h): 13.8 SEER2, 11.2 EER2
- Split Heat Pumps: 14.3 SEER2, 7.5 HSPF2
- Packaged Air Conditioners: 13.4 SEER2, 10.6 EER2
- Packaged Heat Pumps: 13.4 SEER2, 6.7 HSPF2
For other regions of the United States, please refer to the official DOE or ICC documentation for region-specific efficiency standards.
7. Real-World Examples
Here’s how this transition typically plays out:
- A heat pump listed as 15.0 SEER2 roughly corresponds to about 15.5 – 16.0 SEER.
- A split system with 11.7 EER2 may equate to around 12.0 EER.
- On a CF2R form, the installer should enter the converted SEER value in the efficiency field and note the actual SEER2 rating in the comments (“SEER2 rating = 15.0”). This is only for 2019 Title 24 CF1Rs.
This ensures building officials can verify both the rated equipment and the conversion used.
8. What Homeowners, Contractors, and Energy Consultants Should Do
If your project is under the 2019 Energy Code:
- Continue using SEER-based CF1R forms.
- When installing new equipment rated with SEER2, use the CEC conversion table and document both ratings.
If your project is under the 2022 Energy Code:
- Use SEER2/EER2/HSPF2 ratings directly in your CF1R and CF2R forms.
- Double-check that your equipment meets current DOE minimums for California’s region.
Keeping a record of both ratings helps streamline plan checks and avoid re-submittals during Title 24 review.
9. Conclusion: Simplifying the Transition with Accurate Conversions
The shift to SEER2, EER2, and HSPF2 marks a major step toward more realistic and accurate HVAC efficiency standards.
While the new numbers may appear lower, they better represent how systems perform in real California homes.
If you’re documenting equipment under the 2019 Energy Code or just want to compare old and new ratings, use our Conversion Tool above to quickly translate values for Title 24 compliance.
References
- California Energy Commission (CEC) – Blueprint 143: SEER2 Guidance for 2019 and 2022 Energy Code Compliance. Link to CEC Blueprint
- U.S. Department of Energy (DOE) – 2023 Central Air Conditioner and Heat Pump Standards FAQ (October 2022). Download PDF
- International Code Council (ICC) – New 2023 Efficiency Requirements for Air Conditioning Systems: Considerations for Code Officials and the Building Safety Community (December 2022). Read online
- Air-Conditioning, Heating, and Refrigeration Institute (AHRI) – Residential Central Air Conditioners and Heat Pumps: 2023 Regional Standards Overview. View resource
These references provide the official DOE, ICC, and CEC sources that informed this blog’s technical details and regional requirements for SEER2, EER2, and HSPF2 standards.
