Pressure Vacuum Breaker Assembly (PVB)
- A PVB is a mechanical backflow preventer that consists of an independently acting, spring-loaded check valve and an independently acting, spring-loaded, air inlet valve on the discharge side of the check valve. It includes shutoff valves at each end of the assembly and is equipped with test cocks.
- Only one PVB required to serve the whole system; control valves can be located downstream of (after) the PVB.
- PVBs must be installed a minimum of one foot (12") above the highest point of water they serve.
- A City Recognized backflow assembly tester when installed, annually or when moved, or repaired must test PVBs.
- No chemicals or fertilizers may be introduced into an irrigation system containing PVBs.
- No pumps or backpressure on downstream side of (after) a PVB.
- A PVB may be used to isolate health or non-health hazards but is effective against backsiphonage only.