Safety valves which help prevent excess pressure in an installation. They operate automatically and reset at their set pressure. Our stock items have a set pressure of 21 mbar and a relief pressure of 50 mbar; that is to say, they will vent off if a pressure of 50 mbar is reached, resetting the pressure at 21 mbar ; The relief pressure may be adjusted by removing the cap and turning a screw; the relief pressure cannot exceed the set pressure by more than 150 mbar (60" wg). Valves may be mounted in horizontal or vertical pipework.

Threads: BSP female to  ISO 7-1 (Formerly BS 21).

For Natural Gas and LPG.