How is HVAC energy efficiency measured?

The most common measurement of an air conditioner’s  efficiency is called a “SEER”.

“SEER” stands for “seasonal energy efficiency rating.” This measures how much cooling the system will deliver, per dollar that you spend on electricity.

The higher the SEER, the more efficient the energy efficiency will be. Higher-end ACs tend to have a better SEER than economy models, but long-term energy savings can offset the initial expense.

Another common efficiency measurement, often used for furnaces, is the “AFUE”: “annual fuel utilization efficiency.” This is often used for furnaces and boilers, and measures average thermal efficiency.

AFUE ratings are represented as a percentage, with most good furnaces and boilers averaging anywhere from 80% to 96% AFUE.