If you are shopping for a new air conditioner or heat pump, you will see the term SEER2 on every quote and brochure. It is the main number that tells you how efficient a cooling system is. Here is what it means, how it differs from the old SEER rating, and how to decide what efficiency makes sense for your home in Southern California.
What is SEER2?
SEER stands for Seasonal Energy Efficiency Ratio. It measures how much cooling a system delivers over a typical season compared with the electricity it uses. The higher the number, the more efficient the system.
SEER2 is the updated version of that rating, introduced by the U.S. Department of Energy in 2023. The test procedure was changed to better reflect real homes, especially the extra resistance of real ductwork. Because the test is tougher, SEER2 numbers are a little lower than old SEER numbers for the same equipment. A system that used to be labeled around 15 SEER is roughly 14.3 SEER2.
Minimum efficiency in California
California is in the federal “Southwest” region, which has some of the strictest minimums in the country. New central air conditioners installed here must meet minimum SEER2 levels and also an EER2 requirement, which measures efficiency at high outdoor temperatures — important for hot inland areas. Your contractor should only offer equipment that meets current rules. Ask to see the AHRI certificate for the exact matched system being quoted.
SEER2, EER2 and HSPF2 — what each one means
- SEER2 — seasonal cooling efficiency.
- EER2 — cooling efficiency on very hot days. Matters in Burbank, the San Fernando Valley and Santa Clarita.
- HSPF2 — heating efficiency for heat pumps.
- AFUE — efficiency of gas furnaces (for example, 80% or 95%).
Is a higher SEER2 worth it?
Higher-efficiency systems cost more up front and usually save more on electricity each month. Whether the upgrade pays off depends on:
- How much you run your AC. Inland valley homes that cool for many months see bigger savings than homes near the coast.
- Your electricity rates. California electricity is expensive, which makes efficiency more valuable.
- Comfort. Higher-efficiency systems often use two-stage or variable-speed compressors, which run longer at lower speeds. That means more even temperatures and better humidity control.
- Rebates. Utility and state programs sometimes favor high-efficiency heat pumps. Programs change often, so check current offers.
How much can a higher rating save?
A simple way to estimate: the cooling cost changes roughly in proportion to the ratio of the ratings. For example, replacing a very old system rated around 10 SEER with a new system rated around 16 SEER uses about 10/16 of the electricity for the same cooling — roughly 35–40% less. If cooling cost you about $1,000 last year, that could mean savings in the range of $350–$400 a year. Real results depend on the installation, your ductwork, your thermostat habits and your utility rates, but the math shows why upgrading a 15–20-year-old system often pays off.
Efficiency depends on installation, too
A high SEER2 rating only delivers its promise if the system is properly sized, matched and installed. Leaky ducts, poor airflow or an incorrect refrigerant charge can waste a large share of the efficiency you paid for. That is why we check ductwork, airflow and sizing — not just the equipment label — before recommending a system.
New refrigerants
New residential systems are moving to lower-global-warming refrigerants such as R-454B and R-32, replacing R-410A. Older R-22 systems are the most expensive to repair. If your system is old, see our guide on repair vs. replace.
Get a clear comparison
When we quote a new system, we show you options at different efficiency levels with prices side by side, so you can weigh up-front cost against comfort and energy savings. Learn more about AC installation in Los Angeles and our heat pump services. Financing is available for qualified customers.
Get a free estimate on a new system
Orion HVAC serves La Crescenta, Glendale, Burbank, La Cañada Flintridge, Tujunga, Santa Clarita and the San Fernando Valley. Call (323) 736-3737 or book online. You get the price before any work begins, and every repair is backed by our parts and labor guarantee.
