Spill-Resistant Pressure Vacuum Breaker Backflow Prevention Device Assembly – Air Inlet Valve and Drainage
Because supply pressure keeps the air inlet closed, the PVB shall be installed only where water will not cause damage to the area where the PVB is installed. This is not the case with the SRPVB. On startup, the SRPVB air inlet valve will close before the check valve reducing or eliminating the discharge of water on start-up out of the bonnet. Siphon conditions and pressure surges will not cause the SRPVB to discharge water. If the air inlet valve does not seat properly because of dirt or debris located between the air inlet disc and the air inlet seat discharge from the SRPVB may occur. The SRPVB may be installed where limited spillage is not an issue or objectionable. Although the SRPVB is designed to prevent spillage of water, the SRPVB should not be installed in concealed locations or areas where water leakage caused by ware of the internal parts could cause damage to the surround area. If the SRPVB must be installed in an area where water spillage could cause damage, proper drainage shall be provided. The SRPVB must be installed so that the air inlet valve operates in the vertical position. If the SRPVB is not installed according to manufacturer’s specification, it may malfunction and not operate properly.
