The wet alarm valve is a key component of the wet automatic sprinkler system. The pipe network of the system is filled with pressurized water and is in standby working state for a long time. When a fire occurs somewhere in the protected area, the ambient temperature rises and the thermal sensitive element of the nozzle ruptures. The sprinkler sprays water and automatically starts the system to spray water directly to the fire area and send out an alarm signal at the same time. The system is suitable for buildings and structures where the ambient temperature is 4~70°C and can be extinguished with water. It is usually installed in high-rise buildings and garages such as fire-risk production sites, warehouses, hotels, shopping malls, hospitals, office buildings, etc.