Buyer Education | Updated June 2026
SEER2 replaced SEER in 2023. California's floor is 14.3 SEER2. For Sacramento's long cooling season, a 17 SEER2 unit pays back the premium faster than it would in most U.S. cities.
If you have received an HVAC quote recently, you have probably seen SEER2 on the spec sheet. It replaced the old SEER metric in January 2023. It uses a more realistic savings test. California floor for split-system AC under 45,000 BTU is 14.3 SEER2. That is roughly equal to the old SEER 15 standard. Sacramento cooling season runs roughly five to six months. A higher SEER2 rating delivers more monthly savings here than in cities with shorter summers.
SEER2 stands for Seasonal Energy Savings Ratio 2. It measures how much cooling a unit delivers per unit of power over a full season. Higher numbers mean less power per ton of cooling. The new test uses higher static pressure conditions than the old SEER test. So a 14.3 SEER2 unit performs at roughly the same real-world savings as an old 15 SEER unit.
As of January 2023, California requires a floor of 14.3 SEER2 for most split-system residential AC units under 45,000 BTU. Any new unit in Sacramento must meet this floor to pass inspection. Installing a unit below this rating is not permitted.
At 14.3 SEER2, you meet the floor. At 17 SEER2, you use roughly 16% less power per cooling hour. With Sacramento's 5-month cooling season and SMUD or PG&E rates, that savings gap can mean real monthly savings. The premium for a 17 SEER2 unit over a 14.3 model runs $800 to $2,000 based on brand and size.
The old SEER test measured savings at lower indoor static pressure. SEER2 uses an external static pressure of 0.5 inches of water column. This is closer to real-world duct resistance. As a result, a unit SEER2 number is about 5% lower than its old SEER number for the same unit. A unit rated SEER 15 under the old test is now rated roughly 14.3 SEER2.
When comparing older quotes to newer ones, be careful comparing SEER and SEER2 numbers directly. They are not the same scale. Fresh Air estimates always use SEER2 ratings and note the brand and model number. So you can verify specs independently.
The floor SEER2 for most split-system AC units under 45,000 BTU in California is 14.3. This standard took effect January 1, 2023. Units below this rating cannot be installed as new units in California.
14.3 SEER2 meets the legal floor and is a meaningful step above older low-savings systems. For Sacramento homeowners who plan to stay long-term and run their AC five or more months a year, a 17 SEER2 unit often offers a better total cost. The purchase price is higher. But long-term costs are lower.
The difference is often $800 to $2,000 for the same size unit from the same brand family. The exact gap depends on brand tier and tonnage. Fresh Air can show you side-by-side pricing on your free estimate.
Some power rebate programs require a floor SEER2 above the state floor. Check current status and amounts at smud.org or with your power provider before choosing a model.
SEER2 measures savings, not cooling capacity. A higher SEER2 unit uses less power to deliver the same cooling. Comfort depends on correct sizing through a Manual J calc. Fresh Air runs Manual J on every free estimate.
Fresh Air Heating & Air shows you side-by-side SEER2 options on every free estimate. We serve Sacramento, Elk Grove, Folsom, Roseville, Rocklin, and surrounding areas. Call (916) 416-8181 or visit /contact/. Licensed CSLB #945361, insured, since 2010.