The Principle Operation of a Dual Check Valve with Intermediate Atmospheric Vent – Backflow Prevention Device – Flow Capacity
When the DCVwIV is fully pressurized and there is a demand downstream, (dynamic state) the spring loaded check valve are open and the intermediate atmospheric vent closed. The grater the rate of flow (gpm) through the DCVwIV, the grater the check valve will open. As the rate of flow in gallons per minute through the DCVwIV increases, the pressure loss in pounds per square inch increases. Consult manufacture literature or capacity rate for the specific DCVwIV.
