Double Interlock Preaction Valve Assembly

Double Interlock Preaction Valve Assembly

Electric/Electric Release Trim

Model no.: LF-PA-50, LF-PA-80, LF-PA-100, LF-PA-150

& LF-PA-200


  • Size: 50, 80, 100, 150 & 200 NB
  • Solenoid Valve: 24V DC
  • Max Working Pressure: 17.5 kg./
  • System End Connection: Flanged


The Double Interlock Preaction System with Electric/Electric Release is generally used to protect water sensitive areas such as computer rooms, storage areas, refrigerated areas etc., to avoid water damage due to inadvertent flooding of the sprinkler system piping.

In normal condition, preaction system does not contain water in the sprinkler piping. The sprinkler piping contains air pressure for the purpose of supervising its leak tightness.

This system utilizes a Deluge Valve and Riser Check Valve . The Riser Check Valve isolates the Deluge Valve from the system air  pressure. Riser Check Valve provides an air check so that the system can be automatically pressurized with a supervisory air or nitrogen pressure of 18 PSI (1.26 Bar). A supervisory low pressure alarm switch can be set at 6 PSI (0.42 Bar), on decreasing pressure, to indicate whether there are any abnormal leaks in the sprinkler system piping. Loss of air pressure from the system due to accidental leakage will not cause Deluge Valve to open.