RWC Hot Water Automatic Anti Vacuum Valve - 1/2" MBSP - ADMT503001

A compact valve designed for use with hot water heaters to prevent a vacuum forming in installations where there is the potential of the draw-off rate exceeding the rate of flow to the inlet; this can occur in properties with multiple outlets below the base of the hot water heater. The valve contains a check cartridge which under normal conditions is held closed by the system pressure. When a vacuum condition exists, the suction will cause the check cartridge to open and air to flow through, equalising the pressure within the hot water heater.