Description

Viking VXD Double-Interlocked Preaction Systems utilize a Viking Model VXD Deluge Valve controlled by a pneumatic actuator normally held closed by supervisory pressure maintained in the automatic sprinkler system in conjunction with a normally closed electric solenoid valve controlled by an approved system release control panel with compatible detection system. In order for the deluge valve to open and fill the system with water, the electric detection system must activate and the supervisory pressure must be relieved from the system. If the electric detection system (alone) operates due to fire, damage, or malfunction, an alarm will activate but the deluge valve will NOT open. If the sprinkler piping is damaged or a sprinkler is broken or fused, but the detection system has not activated, an alarm will activate but the deluge valve will NOT open. In fire conditions, operation of both the detection system and a sprinkler is required before the deluge valve will open allowing water to enter the system piping.

Electric/pneumatic double interlocked preaction systems are commonly used as refrigerated area systems. They are also commonly used where flooding of the pipe can have serious consequences, and where it is important to control accidental water discharge due to damaged sprinkler piping. Care should be taken since double interlocked preaction systems may not produce flow from opened sprinklers as quickly as single- or non-interlocked preaction systems. Activation of the detection system alone, or operation of a sprinkler alone, will sound an alarm but will NOT cause the system to fill with water.