Viking Preaction System is a sprinkler system employing closed automatic sprinklers connected to a piping system that contains air or nitrogen that may or may not be pressurized. A supplemental detection system (release line) is installed in the same area as the sprinklers. The basic components of a Viking preaction system include a Model E or F series deluge valve and conventional deluge trim (Figure 1), or a Model G-2000P, G-3000P, or G-4000P valve assembly and trim. The associated release trims are unique to the specific type of preaction system desired (Figures 3-6). For systems using a Model E or F series deluge valve, an Easy Riser® Check Valve is also typically added to the riser when supervisory air is required within the sprinkler system piping network. NOTE: The Model G series valve includes an internal check valve, eliminating the need for a separate check valve on the system riser. The G series valve assembly also includes all the necessary trim components for the preaction system operation