3 957N-OSY-FS

Item Number: F111591
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$10,970.51
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When Will it Ship: Contact for Lead Time
Estimated transit time: 2 to 5 Business Days

Brand - Watts
  • Size: 3 inch
  • Weight: 211.0 lb
  • Housing & Sleeve Material: 304 Stainless Steel
  • Shutoff Valves: OSY (Outside Stem and Yoke) Gate Valves
  • Flood Sensor with SentryPlus Alert® Technology Included
  • Maximum Working Pressure: 175 psi
  • Temperature Range: 33°F - 140°F
  • Lead Free* Bronze Test Cocks
  • UL Classified and FM Approved

Description

The Watts 3 Inch Series 957N Reduced Pressure Zone (RPZ) backflow preventer protects potable water systems from contamination in health hazard applications. Featuring OSY resilient seated gate valves and a 304 (Schedule 40) stainless steel housing, this compact assembly is approved for horizontal N pattern installation. An integrated flood sensor with SentryPlus Alert® technology detects excessive water discharge, offering notification capabilities when paired with an add-on connection kit. It is designed for low pressure loss and ease of serviceability. Item number F111591.

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Flood Sensor Connectivity

  • This Watts Series 957 backflow preventer includes an integrated flood sensor with SentryPlus Alert® technology to detect continuous discharge from the relief valve.
  • To enable flood monitoring and alerts, an add-on sensor connection kit is required (sold separately).
  • Connection kit options allow for compatibility with BMS (Building Management Systems) and cellular network communication.
  • The sensor control monitor (available separately) enables integration with BAS (Building Automation Systems) via RS-485 Modbus or the Nexa® platform through Wi-Fi connectivity.
  • When installing a drain line on the Series 957, use 957AG air gaps and attach the air gap brackets directly onto the flood sensor.
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Additional Details

This Watts Series 957 Reduced Pressure Zone assembly backflow preventer, with 3 inch connections, provides protection to potable water systems from contamination due to backpressure or backsiphonage, commonly used in health hazard applications. It features UL Classified and FM Approved outside stem and yoke resilient seated gate valves.
This extremely compact assembly is approved for horizontal N pattern installation. The unit includes a 304 (Schedule 40) stainless steel housing and sleeve, torsion spring check valves, test cocks, and a corrosive resistant stainless steel bottom mounted pressure relief valve.
Flood Sensor with SentryPlus Alert® Technology
  • Includes a flood sensor on the relief valve to detect excessive water discharges.
  • The sensor is installed on the assembly exterior and does not alter assembly functions or certifications.
  • Relays a signal that triggers notification to facility personnel for corrective action, helping limit flooding and costly damage.
  • Flood alerts feature activated with an add-on sensor connection kit (sold separately), compatible with BMS and cellular network communication.
  • When paired with an add-on connection kit, the sensor enables integration with BAS via RS-485 Modbus or the Nexa® platform through Wi-Fi.
Use of the flood sensor does not replace the need to comply with all required instructions, codes, and regulations related to installation, operation, and maintenance of this product, including the need to provide proper drainage in the event of a discharge. An add-on connection kit is required to activate the flood sensor. Without the connection kit, the sensor is a passive component that has no communication with any other device.
Features
  • Replaceable check disc rubber for easy maintenance
  • Extremely compact design
  • 70% Lighter than traditional designs
  • 304 (Schedule 40) stainless steel housing and sleeve for durability
  • Groove fittings allow integral pipeline adjustment
  • Patented torsion spring checks provide lowest pressure loss
  • Unmatched ease of serviceability
  • Bottom mounted cast stainless steel relief valve
  • Available with grooved butterfly valve shutoffs
  • Sensor on relief valve for flood detection
  • Flood alerts feature activated with add-on sensor connection kit, compatible with BMS and cellular network communication

Specifications

  • Size: 3 inch
  • Model: 957N-OSY-FS
  • Shutoff Valves: OSY (Outside Stem and Yoke)
  • Housing & Sleeve Material: 304 (Schedule 40) Stainless Steel
  • Elastomers: EPDM, Silicone, Buna-N
  • Torsion Spring Checks Material: Noryl®, Stainless Steel
  • Check Discs Material: Reversible Silicone or EPDM
  • Test Cocks Body Material: Lead Free* Bronze
  • Pins & Fasteners Material: 300 Series Stainless Steel
  • Springs Material: Stainless Steel
  • Temperature Range: 33°F – 140°F (0.5°C – 60°C)
  • Maximum Working Pressure: 175 psi (12.1 bar)
  • Wetted Surface Lead Content: Less than 0.25% by weight

Approvals

  • Approved by the Foundation for Cross-Connection Control and Hydraulic Research at The University of Southern California (FCCCHR-USC), excluding 10" N-pattern installation as well as 6" and 10" Z-pattern installations
  • AWWA C511-97
  • ASSE 1013
  • CSA B64.4
  • UL Classified (**BFG & OSY Only)
  • FM Approved (**BFG & OSY Only)
  • NSF Certified to NSF/ANSI 61-G

FAQs

What is the primary function of the Watts Series 957N RPZ backflow preventer?

The Watts Series 957N Reduced Pressure Zone (RPZ) backflow preventer is designed to protect potable water systems from contamination caused by backpressure or backsiphonage, especially in health hazard applications.

What type of shutoff valves are included with this assembly?

This assembly features UL Classified and FM Approved OSY (Outside Stem and Yoke) resilient seated gate valves, which are quarter-turn ball valve shutoffs.

How does the flood sensor work and what does it require?

The flood sensor detects excessive water discharges from the relief valve. To activate its alert features, an add-on sensor connection kit (sold separately) is required. Without the kit, the sensor is passive and will not communicate.

What are the material specifications for the housing and wetted surfaces?

The housing and sleeve are constructed from 304 (Schedule 40) stainless steel. The wetted surfaces, including the Lead Free* bronze body test cocks, contain less than 0.25% lead by weight.

What is the maximum operating pressure and temperature range for this backflow preventer?

This backflow preventer has a maximum working pressure of 175 psi (12.1 bar) and operates within a temperature range of 33°F to 140°F (0.5°C to 60°C).

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