Homeowners often see SEER2 highlighted in HVAC proposals. It is an efficiency rating based on seasonal cooling performance under standardized testing, not a prediction of your exact utility bill.
What SEER2 measures
SEER2 relates seasonal cooling output to electrical energy used under a standardized test procedure. A higher number generally indicates greater rated cooling efficiency.
Why SEER2 is not the whole system
Duct leakage, incorrect refrigerant charge, airflow problems, oversized equipment and poor installation can reduce real-world performance even when the equipment has a strong rating.
Compare matched equipment
Ask for exact indoor and outdoor model numbers and confirm the combination is rated together. Comparing only the outdoor-unit label can be misleading.
Climate and usage still matter
Cooling hours, thermostat settings, humidity, insulation and local electricity prices affect operating cost.
Use efficiency inside the full budget
Change the efficiency tier in the HVAC Replacement Cost Calculator and compare the purchase-price effect alongside the rest of the installation scope.