The wet alarm valve is used in systems where water freezing is unlikely. It continuously fills the retard chamber, triggering a pressure switch. Once activated, the system sends an alarm signal and triggers a water-motor gong for a mechanical alert.

It is a pressure valve that contains an alarm and can withstand normal pressure, although it can reach 6/20 bar. It works at medium heat​ (FM/UL ) certificates​

Wet Alarm Valve