Water service vacuum relief valve. Automatically vents a closed system, if vacuum occurs. Allows air to enter a system, relieving a vacuum condition which could syphon the water from the system and burn out a water heater or collapse a tank.

Specification :
Maximum working pressure : 200 p.s.i. (13.8 bar)
Maximum temperature : 121°C
Size : 1/2" BSP male inlet connection
Venting capacity : 425 litres/minute (air)