SEER2 Ratings Explained for San Antonio AC Replacement

SEER2 ratings appear on every air-conditioner quote in San Antonio. Understanding what the number means helps you compare models without overpaying for efficiency you will not use, or underbuying for a long cooling season.

The rating also shows up on your summer bill. CPS Energy adds a peak capacity charge to residential usage above 600 kWh a month from June through September, and air-conditioning run time climbs with the heat. A more efficient system uses fewer of those summer kilowatt-hours to keep the house at the same temperature.

What a SEER2 Rating Measures

SEER2 stands for Seasonal Energy Efficiency Ratio 2. It compares cooling output over a season with the electricity used, under the updated federal test procedure that took effect January 1, 2023. The updated test uses conditions meant to better reflect installed systems, so a model's SEER2 number is usually lower than its old SEER number. Compare SEER2 to SEER2.

Think of it as cooling delivered per unit of electricity. Under the same test conditions, a 17 SEER2 system needs less electricity than a 14.3 SEER2 system to deliver the same amount of cooling.

Why the numbers changed in 2023

SEER2 values come from the Department of Energy's updated test procedure, known as Appendix M1. Carrier explains that the updated test uses higher external static pressure, which accounts for the resistance of ductwork in a real home. That is why the same equipment posts a lower number under SEER2 than it did under SEER. AHRI's summary of the Southeast standard, for example, pairs 14.3 SEER2 with the old 15 SEER.

SEER vs SEER2 on Older Quotes and Labels

If you are comparing an older quote, a listing for a used system or the paperwork for your current condenser, check which metric it uses. A system rated under the old SEER test usually shows a higher number than it would under SEER2, so a "16 SEER" unit and a "16 SEER2" unit do not describe the same efficiency.

Compare SEER2 to SEER2, and ask the contractor to state every option on your quote in SEER2. If your current air conditioner was installed before 2023, its paperwork most likely lists SEER, which makes it look a little more efficient next to new SEER2 equipment than it really is.

Federal Minimums for Texas

For the Southeast region, which includes Texas, AHRI's summary of the federal standards lists at least 14.3 SEER2 for split-system central air conditioners under 45,000 Btu/h and 13.8 SEER2 for larger split systems installed on or after January 1, 2023. Those are floors; many systems sold rate higher.

The Department of Energy's regional standards enforcement page lists Texas in the Southeast region. In the Southeast, split-system air conditioner standards are enforced by the date of installation. Since January 1, 2023, a split system installed in Texas must meet the regional SEER2 standard, even if the equipment was built earlier. Packaged units, where all the major parts sit in one cabinet, follow the manufacture date instead, according to AHRI.

HSPF2 is the heating-season rating for heat pumps, which matters on San Antonio's cold snaps. The Southwest region, which covers Arizona, California, Nevada and New Mexico, adds EER2 requirements on top of SEER2.

SEER2 vs EER2 on the Hottest Days

SEER2 is a seasonal average across a range of test conditions. EER2 is measured at one steady condition, 95°F outdoors, so it shows how efficiently a system runs at full load on a hot afternoon. Long, hot San Antonio afternoons are exactly when your system works hardest, so EER2 is worth reading alongside SEER2.

Two systems with the same SEER2 can have different EER2 values. If your home struggles to stay cool in the late afternoon, or your west-facing rooms run warm, ask for both numbers for the exact equipment combination on your quote.

What Is a Good SEER2 Rating for San Antonio?

There is no single right number. The federal floor for a new split-system air conditioner in Texas is 14.3 SEER2 under 45,000 Btu/h. ENERGY STAR sets its criteria for split-system heat pumps at 15.2 SEER2, 11.0 EER2 and 7.8 HSPF2. Manufacturers sell equipment well above those levels; Carrier, for example, lists residential air conditioners rated up to 21 SEER2.

Because SEER2 is a ratio of cooling to electricity, you can compare levels on paper. Under identical test conditions, the electricity needed for the same cooling drops as the rating rises:

Those are test-condition comparisons, not bill guarantees. Real savings depend on how many hours your system runs, your electricity rate, whether the system is sized correctly and how tight your ducts are. A long cooling season gives a higher-rated system more hours to earn back its extra cost than a mild climate would, but the choice still has to fit your budget and how long you plan to stay in the home.

Higher SEER2 vs Upfront Cost

A higher rating uses less electricity for the same cooling but costs more upfront. Whether it pays back depends on how many hours the system runs, your electricity rate, and whether the system is sized and installed correctly. Ask for operating-cost estimates for each option you are offered.

A practical way to compare: pull last summer's kWh from your CPS Energy bills or My Energy Portal, then ask each contractor to estimate the yearly operating cost of each option using your usage instead of a national average. Because CPS Energy charges more for summer usage above 600 kWh a month, cooling efficiency saves the most in your highest-usage months; see what drives a high San Antonio summer electric bill.

Single-Stage, Two-Stage and Variable-Speed

Single-stage systems run at full output whenever they run. Two-stage and variable-speed systems can run at lower output for longer, which often improves humidity control and comfort, at a higher price.

In a humid San Antonio summer, longer runs at lower output give the indoor coil more time to pull moisture from the air, which can let you stay comfortable at a higher thermostat setting. Staged and variable-speed systems may need a compatible thermostat, so make sure thermostat compatibility is covered on the quote.

Sizing and Ducts Matter as Much as the Rating

An oversized system short cycles and controls humidity poorly, and leaky or undersized ducts waste capacity. A load calculation and a duct check belong in any replacement quote.

The rating on the brochure belongs to a certified combination of outdoor unit and indoor coil. The Department of Energy treats each combination separately, so ask for the certified SEER2 and EER2 of the exact pair on your quote, not the best-case number for the outdoor unit alone.

Ducts deserve the same attention. The Department of Energy estimates that about 20% to 30% of the air moving through a duct system is lost to leaks, holes and poorly connected ducts. A high-SEER2 system feeding leaky attic ducts loses part of what you paid for, so bring ductwork questions into the same conversation as the equipment.

Electrical Checks for a New Air Conditioner

A replacement air conditioner may call for a different breaker size, a new outdoor disconnect or updated wiring, depending on the new equipment's nameplate requirements. Older homes may also need a look at panel capacity, especially if you are adding an EV charger or other large loads around the same time. A licensed electrician should confirm the circuit before the new system starts up. C.S.W. Power Solutions handles electrical panel and circuit work under Texas Electrical Contractor license TECL #31793.

Rebates and Tax Credits

CPS Energy's STEP page lists Home Energy Rebates for central air and heat pumps. Confirm current eligibility and amounts with CPS Energy before you buy.

When checked in October 2026, CPS Energy's HVAC rebate page listed central A/C and heat pump rebates of $90 to $310 per ton. Amounts, tiers and eligibility can change, so confirm the requirements with CPS Energy before you buy.

Federal tax credits work differently. ENERGY STAR describes the central air conditioner tax credit as applying to equipment purchased and installed between January 1, 2023, and December 31, 2025. If a 2026 quote counts on that credit, check with a tax professional before you rely on it.

Questions to Ask on Every AC Replacement Quote

1. What are the certified SEER2 and EER2 ratings for this exact outdoor unit and indoor coil combination?
2. Does it meet the 14.3 SEER2 Southeast minimum for its size?
3. Was the system sized from a load calculation for this house?
4. Were the ducts checked for leaks and size?
5. Does the thermostat need to change?
6. Does the circuit, disconnect or panel need electrical work?
7. Which CPS Energy rebates could apply, and what documentation do they require?
8. Is a permit needed, and who pulls it?

If your current system still runs but struggles, compare these answers with the warning signs that an AC needs repair before you decide to replace it. A single fixable problem, such as a clogged AC condensate drain, is a repair question rather than a replacement decision. For local options, see AC replacement in San Antonio and San Antonio HVAC information.