Fan Brake Horsepower Calculator

Calculate fan brake horsepower and motor size from airflow and static pressure.

Design airflow rate.
CFM
Total static pressure the fan must overcome.
in WC
Fan static efficiency (0.5-0.8 typical).
Belt/drive losses (3-5% belt, 0% direct).
%

Results

Brake Horsepower-HP
BHP with Drive Loss-HP
Recommended Motor-HP
References: ASHRAE Handbook—HVAC Systems & Equipment Ch. 21; AMCA 210/ASHRAE 51