This 4 inch lead free reduced pressure zone backflow preventer assembly prevents the reverse flow of polluted water from entering into the potable water supply due to backsiphonage and/or backpressure. It is ideal for protection in continuous pressure piping applications and at cross-connections identified as health hazards.

Features

• Features a flood sensor with SentryPlus Alert® technology to detect continuous discharge from the relief valve.
• Utilizes advanced ArmorTek® coating technology to resist corrosion of internals.
• Cast iron body construction with patented 3-part advanced epoxy coating system designed to limit both microbial induced (MIC) and exposed metal substrate corrosion.
• Unique patented air-in and water-out design provides high capacity relief valve discharge performance during emergency conditions.
• Domestic non-rising stem (NRS) resilient seated gate valves.
• Includes captured spring check valves, replaceable seats, top mounted test cocks, and a field reversible pressure differential relief valve.
• An add-on sensor connection kit is available to extend flood monitoring on compatible assemblies.
• Integrates with the Sensor Control Monitor to deliver maintenance alerts to BAS via RS-485 Modbus or the Nexa® platform by Wi-Fi connectivity.

How It Operates

• The unique relief valve construction incorporates two channels: one for air, the other for water. When the relief valve opens, the right-hand channel admits air to the top of the reduced pressure zone, relieving the zone vacuum.
• The channel on the left then drains the zone to atmosphere.
• If both check valves foul, and simultaneous negative supply and positive backpressure develop, the relief valve uses the air-in/water-out principle to stop potential backflow.

The installation of a drain line is recommended. When installing a drain line, an air gap is necessary.