SEER2 Ratings Explained
SEER2 ratings describe seasonal cooling efficiency for central air conditioners and heat pumps under the current DOE test procedure. A higher SEER2 indicates more cooling output per unit of electrical energy under the standardized test, but real-world energy cost still depends on runtime, weather, sizing, ducts and installation quality.
What exactly does SEER2 measure?
This page is part of the HVAC Guides library.
Seasonal Energy Efficiency Ratio 2
DOE defines SEER2 as total cooling delivered during an annual cooling season divided by the electrical energy consumed during that same seasonal test.
Generally means higher rated cooling efficiency
When otherwise comparable systems are considered, a higher SEER2 generally represents lower electrical input for the same standardized seasonal cooling output.
Texas is part of DOE's Southeast regional standards area.
SEER became SEER2
DOE changed the residential HVAC test procedure and nomenclature beginning in 2023. SEER and SEER2 values should not be compared as though they are identical test metrics.
Texas regional rules matter
DOE places Texas in the Southeast region for applicable split-system central air-conditioner regional standards.
ENERGY STAR currently uses 15.2 SEER2
Current ENERGY STAR criteria list at least 15.2 SEER2 for qualifying residential split-system and single-package central AC equipment, along with applicable EER2 requirements.
Installation can erase expected benefits
Incorrect airflow, refrigerant charge, sizing and duct leakage can reduce real-world performance.
Use SEER2 as one part of the buying decision.
Calculate estimated savings
Use the SEER2 savings calculator to compare two efficiency ratings.
Compare system efficiencies
Use the HVAC efficiency comparison tool.
Compare old and new AC
Run operating assumptions through the old AC vs new AC calculator.
Consider replacement cost
Compare equipment spending with the Texas AC replacement cost guide.
Repair versus efficiency upgrade
Use our repair vs replace AC guide.
Estimate payback
Use the HVAC payback calculator rather than assuming the highest rating always pays back fastest.
If efficiency concerns began with a rising utility bill, compare the high HVAC electric bill guide. All calculators are available in the HVAC Tools hub.
Official efficiency sources.
DOE SEER2 Definition
DOE explains the shift to SEER2 and current test nomenclature. Review DOE.
DOE Regional Standards
Texas is included in the Southeast regional standards area. Review regional standards.
ENERGY STAR Criteria
Current certification criteria use SEER2 and EER2. Review criteria.
Quality Installation
ENERGY STAR highlights sizing, airflow, charge and ducts. Review installation guidance.
Comparing a new high-efficiency AC?
Request HVAC help and provide your Texas city or ZIP plus the equipment or efficiency ratings you are comparing.
Common SEER2 questions.
What does SEER2 mean?
It measures seasonal cooling output divided by electrical energy consumption under DOE's current test procedure.
Is higher SEER2 always better?
It indicates higher rated seasonal cooling efficiency, but price, runtime, installation quality and actual usage still matter.
Is SEER2 the same as SEER?
No. SEER2 uses the newer DOE test procedure and should not be treated as numerically identical to older SEER ratings.
Does Texas have regional AC efficiency rules?
Yes. Texas is included in DOE's Southeast region for applicable central AC regional standards.
Will a higher SEER2 cut my bill by a specific percentage?
Not automatically. Savings depend on the systems compared, runtime, electricity price, weather and building load.
How can I compare two ratings?
Use the SEER2 savings calculator.
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