Confused by SEER2 vs SEER on new AC systems in Arizona? Sapper HVAC explains the difference and what it means when comparing systems for your Phoenix metro home.
What Is SEER2 and How Is It Different From SEER?
If you've been shopping for a new air conditioning system in Phoenix, Chandler, Mesa, Gilbert, or anywhere in the Phoenix metro area recently, you've probably noticed that new systems now display a SEER2 rating instead of — or alongside — the old SEER rating. Here's exactly what changed and what it means for Arizona homeowners.
A Quick Recap: What Is SEER?
SEER (Seasonal Energy Efficiency Ratio) measures how efficiently an air conditioner converts electricity into cooling over an entire cooling season. Higher SEER = more cooling per dollar of electricity consumed. This rating has been the industry standard since the 1990s.
Why Did the Industry Switch to SEER2?
The Department of Energy updated the testing methodology for AC efficiency ratings in 2023 to better reflect real-world operating conditions. The old SEER test used lower external static pressure — essentially testing systems in easier-than-real-world conditions. The new SEER2 test uses higher static pressure that more accurately represents how systems perform in actual homes with real ductwork.
The result: SEER2 ratings are approximately 4–7% lower than SEER ratings for identical equipment. The equipment didn't get less efficient — the measurement just got more accurate.
How to Convert Between SEER and SEER2
- Old SEER 14 ≈ SEER2 13.4
- Old SEER 15 ≈ SEER2 14.3
- Old SEER 16 ≈ SEER2 15.2
- Old SEER 18 ≈ SEER2 17.2
- Old SEER 20 ≈ SEER2 19.0
- Old SEER 21 ≈ SEER2 20.0
What Are the New SEER2 Minimums for Arizona?
As of January 1, 2023, the minimum SEER2 for new split-system AC units sold in the Southwest region (including Arizona) is:
- Split-system AC (residential): 14.3 SEER2 minimum
- Single-package units: 13.4 SEER2 minimum
Equipment rated below these minimums can no longer be sold as new in Arizona. If a contractor is offering you a "great deal" on a 13 SEER system, it's old inventory that predates the new regulations — be cautious.
Our Recommendation for Phoenix Metro Homeowners
- Minimum: 15 SEER2 for budget-conscious replacements
- Best value: 16–18 SEER2 for homeowners who will be in the home 5+ years
- Best efficiency: 19–22 SEER2 for maximum APS/SRP bill savings and APS rebate eligibility
All systems we install are current SEER2-compliant. We serve Phoenix, Chandler, Gilbert, Mesa, Tempe, Scottsdale, Glendale, Peoria, Surprise, Queen Creek, Apache Junction, Buckeye, Anthem, New River, Maricopa, Casa Grande, and Florence.
Contact Sapper HVAC to discuss which SEER2 rating makes the most sense for your home and budget.