Wet Pipe Systems
The Wet Pipe Sprinkler System is the simplest and most common type of fire sprinkler installation. Since the piping system stays filled with water, they are frequently installed in factories, warehouses, office buildings, retail stores, and residences where the potential for freezing does not exist. This system employs automatic and closed-type sprinklers heads that contain either a heat-responsive glass bulb or a fusible element. The water is contained in the pipes until such time as the heat from the fire activates the heat sensitive element, causing it to release the water through the orifice to the heat source.
Contrary to many perceptions of automatic sprinkler systems, in a Wet Pipe System the only sprinkler heads that will discharge water are those where the temperature reaches the point to activate the heat sensitive element. Water will not be discharged from sprinkler heads where the heat and fire do not exist. Although we have all seen sprinkler systems depicted by television and movies, where every sprinkler head on a system discharges due to a fire in a wastebasket. This simply is not an accurate depiction of a wet pipe sprinkler system.