Another Check Valve Fail on a PVB
The seat of the PVB is part of the body and damaged. In this case the repair kit was not effective. This is a replacement. The repair parts are very handy to have on hand though. Most of the time the rubber kit or check kit will fix this. Occasionally, the seat becomes damaged and can not be replaced as the replaceable seats in the Watts 800M4 and Conbraco PVB 4A. USC has made a requirement for all new approvals to have replaceable seats.