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ECS Protector Nitrogen Inerting Vent

  • For wet pipe fire sprinkler systems
  • Designed specifically for wet pipe nitrogen inerting (WPNI)
  • Rated up to 175 PSIG
  • FM Approved
  • U.S. Patent Nos. 8,636,023 and 9,526,933

This FM Approved product is designed to allow controlled venting of trapped gases within a fire sprinkler system when the system is filled with water after wet pipe nitrogen inerting (WPNI) has been performed. The vent, located remotely on the system, automatically releases the gas when appropriate. This device also satisfies the venting requirements in the 2016 edition of NFPA 13.

Click here to see why a vent is necessary for Wet Pipe Nitrogen Inerting.


  • During the nitrogen inerting process the vent remains closed to prevent discharge of nitrogen gas used to displace oxygen, which causes corrosion
  • Only one (1) vent needed per fire sprinkler system to effectively perform WPNI
  • Once 98% nitrogen concentration in piping is achieved for corrosion control, the vent continues to provide venting of trapped gas that may migrate through the system over time
  • Helps reduce false waterflow alarms created by large pockets of compressed gas in the sprinkler system
  • Vent automatically closes when water has reached the device
  • Redundant float valve design eliminates need to plumb to drain


  • Nitrogen Inerting Vent (model PAV-WN) also includes nitrogen injection port
  • Pressure regulating device integrated on gas discharge piping assembly to prevent discharge during WPNI
  • Gas sample port provides location to verify nitrogen concentration of fire sprinkler system
  • Pressure gauge designed to be visible from below the vent up to 30 feet away to indicate if primary float valve has failed
  • Temperature range: 40-120 degrees F (4.5-49 degrees C)
  • FM Approved per Approval Standard 1344

Optional Remote Inerting Station

The ECS Protector Remote Inerting Station (RIS-1) allows for all nitrogen inerting functions of the Nitrogen Inerting Vent (PAV-WN) to be provided at a floor-accessible location, eliminating the need for ladders, lifts, or additional labor for access to the PAV-WN to complete the WPNI process.

The RIS-1 provides the following functionality to complete the WPNI process:
  • Nitrogen gas purity sampling
  • System pressure monitoring
  • Trapped water removal from vent assembly
  • Control exhaust gas when venting into atmosphere is impractical or undesirable
PAV-WN connections to RIS-1

Installation Notes

  • Install vent assembly remotely on system and nitrogen injection port at riser above system control valve
  • If a location for the vent isn’t provided on project design documents, vent can be installed at an accessible remote high point on the system where pressure gauge is visible from below
  • Do NOT install in location downstream of water trap
  • Install optional RIS-1 on a wall or vertical surface near the vent assembly in an accessible location
  • Make proper connections between vent assembly and RIS-1 according to connections guide; note that y-strainer connection will be exposed to normal system pressure