See the estimated annual cooling cost, energy reduction and simple payback before paying thousands more for a higher rating.
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Compare an existing AC with a proposed SEER2 rating using your system size, cooling climate and electricity rate. Add the efficiency upgrade premium to estimate simple payback.
Instant result · no email requiredA rating comparison assumes equal load and operating conditions. Duct leakage, sizing, humidity control, fan energy, maintenance and utility-rate changes are not captured by the simple seasonal formula.
SEER2 is a laboratory seasonal cooling-efficiency ratio: seasonal cooling delivered in BTU divided by electrical energy in watt-hours under the test procedure. A higher number means less rated electricity for the same modeled cooling load. The Department of Energy changed the test conditions and labels from SEER to SEER2 in 2023, so an old SEER number and a new SEER2 number are not perfectly like-for-like.
The calculator converts an older SEER entry to an approximate SEER2-equivalent basis, then applies the entered capacity and equivalent cooling hours. It is intentionally transparent: annual load divided by the rating gives approximate electricity, and electricity multiplied by the entered utility rate gives cost. That makes the tool useful for comparing proposals while keeping the limitations visible.
The rating does not repair leaky attic ducts, correct oversized equipment, improve insulation or guarantee proper refrigerant charge and airflow. A modest correctly sized system with sealed ducts can outperform a premium unit attached to a poor distribution system. Fan energy, humidity targets, thermostat schedules, maintenance and weather also move actual bills.
Efficiency ratios make percentage comparisons straightforward, but percentage alone can exaggerate the buying decision. A 20% reduction on a $400 annual cooling cost is $80; the same reduction on a $2,000 cooling cost is $400. Enter a realistic climate band and your own electricity rate, then compare the dollar result with the actual equipment premium.
Also separate cooling efficiency from the features bundled with it. A premium proposal may add variable-capacity comfort, sound reduction, controls or longer labor coverage. Those can have value, but describing the whole premium as an energy investment makes the payback look less honest.
For a verified equipment comparison, request the complete condenser, coil and furnace or air-handler model numbers. Search the matched combination in the AHRI certified equipment directory. A condenser’s headline efficiency is not automatically the rating of every indoor-unit combination.
Enter only the extra price for the higher-efficiency option—not the full replacement price. Divide that premium by the annual savings for a simple payback. The result ignores future energy inflation, financing, maintenance and equipment life, so it is a screening tool rather than an investment forecast.
Hot climates and expensive electricity create more annual cooling savings. A short northern cooling season can make a large efficiency premium hard to recover, even when the percentage reduction looks impressive. Comfort features such as quieter operation, better humidity control or variable capacity may still justify the upgrade, but they should be priced separately from energy savings.
Ask for the AHRI reference, rated capacity, SEER2 and EER2, staging or modulation, sound data, thermostat requirements, duct corrections, commissioning measurements and the cash-price difference. Compare the total installed range in the HVAC replacement cost calculator and estimate likely tonnage with the AC size calculator.
For an independent public comparison, ENERGY STAR also provides a heating and cooling savings calculator. Different assumptions can produce different answers; that is a reason to inspect the inputs, not to choose the highest saving.
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