What is the difference between SEER and SEER2?

SEER2 is the current efficiency metric (effective 2023) that replaced SEER. It uses the same ratio of seasonal cooling output to energy input but tests under higher external static pressure, which better reflects real ductwork. SEER2 numbers run roughly 4.5% lower than the old SEER for the same equipment, so do not compare a SEER rating directly against a SEER2 rating.

Is a higher SEER2 worth the cost?

Higher SEER2 saves energy every cooling hour, but payback depends on your climate and electricity rate. In hot regions with long cooling seasons and high rates, jumping from 14.3 to 18+ SEER2 can pay back in a few years; in mild climates the savings are smaller and the premium may not recover before the equipment ages out. Run your own load and rate numbers.

SEER vs HSPF Calculator — Heat Pump Savings

What does HSPF2 measure?

HSPF2 (Heating Seasonal Performance Factor 2) measures a heat pump’s seasonal heating efficiency — total heating output in BTU divided by watt-hours consumed over the season, under the updated 2023 test conditions. Higher HSPF2 means lower heating bills. Like SEER2, HSPF2 values are a few percent lower than the old HSPF, so compare ratings on the same scale.

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Use the SEER vs HSPF Calculator — Heat Pump Savings to get an exact answer for your inputs.

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What does HSPF2 measure?

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