David Wickersham cares about the health of our community. Being an ASSE Backflow Protection Assembly Tester and Master Plumber, he tests, rebuilds, and installs backflow assemblies. Whether it is a high or low hazard device, it is tested with accuracy with the leading testing instruments in this specialty field of plumbing.
Reduced Pressure Zone Assembly (High Hazard)
RPZ backflow preventers consist of two independent check valves. ... An RPZ provides the best level of protection because it has a built-in relief valve, which will open up and actually dump the backflowing water out of the valve, in order to prevent any chance of contaminated water re-entering the water supply
Double Check Valve Assembly (Low Hazard)
A double check backflow device (DC) is the simplest and most common type of device. It has two check valves in a completely closed body — two layers of backflow protection. No matter how large the valve is, all DCs are equipped with 1-pound springs that hold the check valves closed during a backflow situation.
Pressure Vacuum Breaker (Irrigation)
A PVB is a testable 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.