HVAC & Refrigeration

Basic

Energy Efficiency Ratio (EER)

Cooling capacity in BTU/h per watt of power — a common AC rating.

Formula

EER = \frac{BTU/h}{W}

Live Calculator

Members

Variables

EEREfficiency ratio

BTU/hCooling output

WPower input (W)

Example

12,000 BTU/h at 1000 W: EER = 12

Did You Know?

EER multiplied by 0.293 converts to the dimensionless COP.

hvac eer rating

Share this formula

More in HVAC & Refrigeration

Sensible Heat Load

Heat needed to change air or water temperature without a phase change.

Latent Heat Load

Heat absorbed or released when moisture condenses or evaporates — the hidden load air conditioners fight.

Coefficient of Performance (Cooling)

Cooling delivered per unit of work input — higher is more efficient.

Refrigeration Tons

Cooling capacity in tons, where one ton removes 12,000 BTU/h.

Airflow (Sensible)

Air volume flow needed to carry a sensible heat load (imperial units).

Carnot COP (Refrigerator)

Maximum possible cooling efficiency between two temperatures (in kelvin).