Inches of water column measures small pressures in HVAC, gas and ventilation; psi is the general pressure unit. One inch of water is about 0.036 psi.
For HVAC
Measure the pressure.
Digital manometer
Read water-column pressure.
HVAC gauge set
Diagnose systems fast.
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Frequently asked questions
How many psi is an inch of water?
One inch of water column equals 0.0361273 psi.
Where is inches of water used?
Gas appliance pressures, duct static pressure and manometer readings.