Waterflow Detector

The Safe Signal WFDNFT waterflow detector is designed for primary signaling in systems that use CPVC fittings

The new WFDNF Series waterflow detectors from Safe Signal consists of a rugged, NEMA 4-rated enclosure that is more damage resistant than previous metal designs. The waterflow detector is designed for both indoor and outdoor use, with the widest available temperature range, from 32°F to 150°F.

The WFDNFT with a threaded tee adapter fits 1”, 1¼”, 1½”, and 2” brass and copper threaded tees, in addition to 1” and 1½” CPVC tees. Clearly marked plastic paddles are included to fit the different installation configurations.

UL-listed models are equipped with tamper-resistant cover screws to prevent unauthorized entry. Inside, two sets of SPDT (Form C) synchronized switches are enclosed in a durable terminal block with an layout designed to make wiring easy. The wire-ready COM terminals are on a different elevation with a large barrier between switches and easy-to-read, raised, textured lettering. An optional cover tamper switch securely snaps into place, no tools required.

The WFDNFS and WFDNFT incorporate a mechanical time delay feature that minimizes the risk of false alarms due to pressure surges or air trapped in the fire sprinkler system. The large and easy-to-turn timer dial makes setting the waterflow detector easy with high-contrast, pad-printed markings. The dial offers three tabs to help with turning: the largest tab is located on the dial position for approximately 60 seconds and a notch in the dial indicates approximately 30 seconds, making the detector easy to set in dimly lit locations.

The WFDNF series is designed for accuracy and repeatability. Detectors also offer improved performance during vibration in riser applications where detectors are exposed to a large in-rush of water.


  • WFDNFT has a NPT threaded adapter for connection to 1”, 1¼”, 1½” and 2” metal tees and 1” and 1½” CPVC tees
  • Directional cover allows installers and inspectors to easily see the direction of flow • UL-listed models are NEMA 4 / IP 54 rated
  • Cover is lightweight, unpainted and corrosion resistant
  • Sealed retard mechanism immune to dust and other contaminants
  • Less exposed metal reduces shock hazard, plastic cover acts as insulator and is resistant to arcing
  • Visual switch activation
  • Audible switch activation (73 dBA)
  • Field-replaceable timer/switch assembly
  • Accommodates up to 12 AWG wire
  • Switch synchronization activates both alarm panel and local bell or horn strobe
  • Tamper-resistant cover screws
  • Wire-ready terminals
  • Improved wiring with new terminal block layout
  • Snap-in optional cover tamper switch

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