Viking supervised VXD Single-Interlocked Preaction Systems utilize a Viking Model VXD Deluge Valve and a pneumatically pressurized automatic sprinkler system. This feature helps prevent undetected leaks. Single-Interlocked Preaction Systems are commonly used where the sprinkler system piping and/or sprinkler may be subject to damage. If the system piping or a sprinkler is damaged, supervisory pressure is reduced and a “low air” supervisory is activated. The electrically controlled preaction systems include an electric solenoid valve controlled by an approved release control panel (sold separately) with compatible detection system (sold separately). In fire conditions, when the detection system operates, the system release control panel energizes the solenoid valve open, causing the deluge valve to open. The sprinkler system fills with water. If any sprinklers have opened, water will flow from the system. If sprinklers have not opened, water will be in the sprinkler system piping when the sprinkler operates. A sprinkler must open before water flows from the system.

Pre-Trimmed Riser (PTR) packages come completely assembled and ready to install. These packages include the Model VXD deluge valve with trim, a riser check valve, additional components as shown below, and come with galvanized pipe and groove/groove connections only. 
The Pre-Trimmed Riser packages include the following components:
• Model VXD valve 
• Riser check valve
• completely assembled trim 
• electric release solenoid 
• water supply control valve 
• pressure gauges for air and water
• grooved couplings
• water flow and air supervisory pressure switches 
• complete drain manifold with hoses and drain cup

Each configuration can be ordered with a monitored or non-monitoroed release solenoid. The monitored solenoid is a new option, which offers an NFPA 13 solenoid monitoring-compliant solution.