Pressure Vacuum Breaker (PVB) Parts

PVBs should be installed about 12 inches above the highest point in the system they protect, typically above ground level. This height allows the device to function correctly by preventing back-siphonage. The PVB valve should also be easily accessible in case of emergencies.

In many areas, a PVB must be tested annually by a certified backflow tester. Local plumbing codes and water utilities require testing to ensure the device properly prevents contaminated water from flowing back into the drinking water supply. If it fails the test, it must be repaired or replaced. Check with your local municipality or water provider, since requirements vary by location.

A pressure vacuum breaker will usually reduce water pressure, but only by a small amount. The internal check valve creates minor resistance as water flows through the device. Still, in most lawn irrigation systems, you won’t notice a significant pressure drop. However, if the PVB is undersized, clogged, or failing, it could cause a more noticeable reduction in pressure.

PVBs can fail due to wear, debris, or freezing temperatures. Sediment and buildup can cause the internal components to stick or wear out, while freezing can crack the assembly, leading to leaks. Consider applying for an annual inspection and maintenance to ensure that your backflow preventer functions properly.