Water Balance Calculator

Calculate water flow rate from differential pressure measurement across a balancing valve or calibrated balancing cock.

Nominal valve diameter
inches
Measured pressure drop across valve
psi
From manufacturer data, typical: 1" = 25, 2" = 100, 3" = 250
Specified design flow
GPM

Results

Calculated Flow Rate-GPM
Deviation from Design-%
Balance Status-
References: ASHRAE 111, AABC National Standards for TAB, Hydronic System Balance Procedures