Double Check Valve Assemblies prevent the backflow of contaminated water into the potable water supply. It consists of a bronze (1/2 to 2 in) or fused epoxy coated cast iron (2 1/2 to 3 in) body construction that is easy to maintain and service. Watts Series 007 is ideal at referenced cross-connections identified as non-health hazard
applications. Check with local inspection authorities for installation requirements. Maximum Working Pressure: 175psi (12.06 bar).

The Double Check Valve assembly is an approved device for most irrigation systems. The Double Check Valve assembly is very accessible and can be obtained at most hardware stores, with the plumbing supplies or irrigation supplies. Home Depot, Sutherlands or Lowes should stock a Double Check Valve Assembly. The Double Check Valve Assembly will consist of a solid brass body approximately 7 to 9 inches long. It will contain two internal spring loaded check valves with two
turn-off valves, one at each end. It will also have four test cocks on the side of the valve for testing purposes.

When inspecting a hot water boiler system, always look for backflow protection. The device should be located somewhere between the pressure-reducing valve and the water service connection. When installing a Backflow Preventer with Intermediate Atmospheric Vent, a common mistake is to locate it on the low pressure side of the system. When installed on the low side, the device will typically drip water from the vent as it needs about 25 pounds of pressure to function properly. Because of the drip, the vent gets plugged. Installing the device on the low side of the system and/or plugging the vent can keep the backflow preventer from working properly. Be
sure to recommend further evaluation by a qualified professional if you discover an improperly installed, plugged, dripping or missing backflow preventer on a hot water boiler system.