A Viking Non-Interlocked Preaction system utilizes a Viking Deluge Valve to control water flow into system piping equipped with closed sprinklers. Under normal operating conditions, the sprinkler piping is supervised with pressurized air or nitrogen to ensure against undetected leaks. Viking Non-Interlocked Preaction Systems are recommended for very large dry systems, which exceed the capacity normally permitted on a dry valve. Non-Interlocked Preaction Systems are designed so the deluge valve will open when EITHER the detection system operates OR a loss of pneumatic pressure in the sprinkler system occurs. When the deluge valve opens, water will flow into the sprinkler piping and out of any open sprinklers and any other opening on the system.