Why it matters to you
Greater Houston averages about 3,288 cooling degree days a year against 1,266 heating degree days, so cooling efficiency drives most of a home's HVAC electricity use. By rating arithmetic alone, a 16 SEER2 system uses about 11% less electricity than a 14.3 SEER2 one for the same cooling (1 − 14.3/16); your actual bill also depends on your rate, thermostat habits, ductwork and how the system was sized.
Practical guidance
Ask for the outdoor and indoor model numbers on every quote and look up that exact matched pair in the AHRI Directory, because the SEER2 rating belongs to the combination, not the outdoor unit alone. Compare SEER2 alongside compressor type and sizing, not by itself.
How SEER2 options compare
| SEER2 rating | Where it sits | Electricity vs. 14.3 SEER2 for the same cooling (rating arithmetic: 1 − 14.3/x) |
|---|---|---|
| 14.3 | Federal Southeast minimum, split AC under 45,000 Btu/h | Baseline (0%) |
| 15.2 | One step above the minimum | About 6% less |
| 16 | Mid-efficiency tier | About 11% less |
| 17 | Higher-efficiency tier | About 16% less |
| 18+ | High-efficiency tier, often two-stage or variable-speed | About 21% less at 18; more above 18 |
What is the minimum SEER2 rating for a new AC in Texas?
Texas is in the Department of Energy's Southeast region. Since January 1, 2023, a new split-system air conditioner there must be rated at least 14.3 SEER2 below 45,000 Btu/h and at least 13.8 SEER2 at 45,000 Btu/h and above. Split-system heat pumps must reach 14.3 SEER2 nationwide.
How much less electricity does a higher SEER2 system use?
The rating arithmetic is 1 − (old SEER2 ÷ new SEER2) for the same cooling load. Against a 14.3 SEER2 baseline, that works out to about 6% less at 15.2, about 11% less at 16, about 16% less at 17 and about 21% less at 18. That is a ratio of ratings, not a bill estimate: real use depends on your rates, ductwork, installation quality and thermostat settings.
Is SEER2 the same as the old SEER number?
No. SEER2 uses the DOE's M1 test procedure, which assumes higher external static pressure to better reflect real ductwork, so the same equipment scores lower in SEER2 than it did in SEER. That is why the Southeast minimum is written as 14.3 SEER2 rather than the older 15 SEER figure. Compare SEER2 to SEER2 only.
Does a higher SEER2 rating mean better humidity control?
Not by itself. Higher SEER2 ratings often come from two-stage or variable-speed compressors, and those longer, lower-output run cycles tend to remove more moisture, which matters in humid Houston. But the number on its own does not describe humidity performance, so ask what compressor and blower type a quoted system uses.
Where do I find a system's real SEER2 rating?
Look up the exact outdoor and indoor model numbers together in the AHRI Directory of Certified Product Performance. The certified rating applies to that matched combination, so a high-rated condenser paired with a mismatched coil may not deliver its headline number. Ask for the AHRI reference number on your quote.
Sources
- eCFR, 10 CFR 430.32 — Energy and water conservation standards
- U.S. Department of Energy, 2023 Central Air Conditioner and Heat Pump Standards FAQ (October 5, 2022)
- NOAA NCEI, U.S. Climate Normals 1991–2020, Houston Intercontinental Airport (USW00012960)
- AHRI Directory of Certified Product Performance