WET SYSTEM VALVE ASSEMBLIES
The wet system valve assemblies is the easiest and most popular sprinkler system and it is generally installed in those areas that are not subject to freeze. The operating principle is very simple: the wet alarm valve works like a standard check valve but it also generates alarms when operating; this feature is typical of all sprinkler systems. Both upstream and downstream valve tubes are filled with water, the crash of a sprinkler makes the system operate immediately against the fire. The system consists of the check valve, wet alarm and hydraulic alarm bell. The wet systems are the most reliable; it is very easy to use them and the costs for installation and maintenance are very cheap.
DRY SYSTEM VALVE ASSEMBLIES
The dry system valve assemblies is installed in those areas subject to freeze or in loading areas or none Air Conditioned parking. The operating principle is similar to the principle of wet systems, the only difference being that upstream the alarm valve, in the distribution system in the protected area, the tubes are not filled with water but with compressed air or nitrogen. The crash of a sprinkler generates a pressure fall which makes the alarm valve open so that the water can reach the distribution valve and extinguish the fire. All the components are manufactured in order to let the valve open rapidly so that an immediate effective action against the fire is guaranteed. Such components like the accelerator give even better results in the operating time speed.Although they are more complicated than the west systems, their manufacturing quality guarantees constant performances over the years and cheap maintenance costs.
THE PRE-ACTION SYSTEM
is specially manufactured for those applications where it is determinant to avoid an accidental operation of the system or replacement of large dry sprinkler system to make them operate faster. These systems are excellent for bookshops, valuable documents archives and refrigerating rooms. Those systems using a single interlock device need a detection device before the water reaches the distribution tubes and the sprinklers. This system prevents from getting wet because of accidental breaks. Water can flow in the protected area only when the detection device alarm is activated.In the double interlock device systems, before the water reaches the distribution system, both the detector and the sprinkler crash are needed.This scheme guarantees an even higher protection against any damage caused by accidental discharges.