Efficiency
Understand SEER, HSPF, AFUE, and efficiency ratings
6 articles
Calculators
Guides & References
AFUE Rating
If you've ever looked at the yellow EnergyGuide label on a furnace and wondered what that AFUE percentage actually means for your wallet, you're not alo...
CADR Rating
CADR (Clean Air Delivery Rate) measures how many cubic feet of clean air a purifier delivers per minute. Every CADR label shows three numbers: one for s...
EER, EER2, CEER, and IEER Ratings Explained
If you've ever shopped for an air conditioner and run into a wall of efficiency acronyms, you're not alone. EER, EER2, CEER, IEER — they all measure coo...
Heat Pump Efficiency vs Temperature
That advice was probably correct 10 years ago. It isn't anymore.
HSPF and HSPF2 Rating
Here's the deal: those two heat pumps might be equally efficient — or even the same unit. The difference is the testing standard, not the hardware.