3 957Z-OSY-FS

Item Number: F111597
1 1
$10,971.17
Special Order
When Will it Ship: Contact for Lead Time
Estimated transit time: 2 to 5 Business Days

Brand - Watts
  • Nominal Size: 3 inch
  • Weight: 211.0 lb
  • Assembly Type: Reduced Pressure Zone (RPZ)
  • Housing & Sleeve Material: 304 Stainless Steel
  • Shutoff Valves: UL/FM Approved OSY Resilient Seated Gate Valves
  • Features: Integrated Flood Sensor with SentryPlus Alert Technology
  • Installation Pattern: Z-Pattern Orientation
  • Maximum Working Pressure: 175 psi
  • Certifications: AWWA C511-97, ASSE 1013, CSA B64.4, UL, FM, NSF/ANSI 61-G

Description

The Watts 3 inch 957Z-OSY-FS Reduced Pressure Zone (RPZ) assembly backflow preventer protects potable water systems from contamination caused by backpressure or backsiphonage. This lead-free device features a 304 stainless steel housing and UL/FM Approved OSY resilient seated gate valves. Its compact, Z-pattern design is approved for horizontal installation. A built-in flood sensor with SentryPlus Alert technology detects relief valve discharge, offering early notification when paired with an optional connection kit for BMS, cellular, or Wi-Fi integration. This assembly has a maximum working pressure of 175 psi and is certified by AWWA, ASSE, CSA, UL, FM, and NSF/ANSI 61-G.

Help Me Connect

Installation & Compatibility

This Watts Series 957 Reduced Pressure Zone assembly is designed for horizontal Z pattern installation. It features groove couplings for ease of installation and pipeline alignment with compatible grooved pipe systems. The integrated flood sensor can be activated with an add-on sensor connection kit, allowing compatibility with Building Management Systems (BMS), cellular networks, or integration with a Sensor Control Monitor for communication via RS-485 Modbus or the Nexa platform (Wi-Fi).

View full details

Additional Details

The Watts 3 inch 957Z-OSY-FS Reduced Pressure Zone (RPZ) assembly backflow preventer provides essential protection for potable water systems from contamination due to backpressure or backsiphonage. This compact and lightweight assembly is suitable for health hazard applications and is approved for horizontal Z pattern installation.

This assembly integrates a flood sensor with SentryPlus Alert technology to detect continuous discharge from the relief valve. When used with an optional add-on connection kit, the sensor activates to relay alerts, limiting potential flooding and costly damage.

Construction & Features

  • Features a 304 (Schedule 40) stainless steel housing and sleeve for durability.
  • Includes UL Classified and FM Approved outside stem and yoke (OSY) resilient seated gate valves.
  • Incorporates a corrosive resistant stainless steel bottom-mounted pressure relief valve.
  • Equipped with patented torsion spring checks designed for low pressure loss and ease of serviceability.
  • Replaceable check disc rubber and reversible silicone or EPDM check discs.
  • Extremely compact design, up to 70% lighter than traditional designs, allowing for smaller enclosure use.
  • Groove couplings facilitate easy installation and pipeline adjustment.
  • Lead-free bronze test cocks.
  • Add-on sensor connection kit enables compatibility with BMS and cellular network communication, or integration with a Sensor Control Monitor for BAS via RS-485 Modbus or Nexa platform via Wi-Fi.

Notice: An add-on connection kit is required to activate the flood sensor's communication features. Without the kit, the sensor functions as a passive component with no external device communication. Watts is not responsible for alert failures due to connectivity issues, power outages, or improper installation.

Specifications

General

  • Brand: Watts
  • Series: 957 Reduced Pressure Zone Assembly
  • Model: 957Z-OSY-FS
  • SKU: F111597
  • Assembly Type: Reduced Pressure Zone (RPZ)
  • Nominal Size: 3 inch
  • Pattern: Z-Pattern

Materials

  • Housing & Sleeve Material: 304 (Schedule 40) Stainless Steel
  • Shutoff Valve Type: Outside Stem and Yoke (OSY) Resilient Seated Gate Valves
  • Relief Valve Material: Cast Stainless Steel
  • Test Cocks Material: Lead Free* Bronze
  • Elastomers: EPDM, Silicone, Buna-N
  • Torsion Spring Checks Material: Noryl®, Stainless Steel
  • Check Discs Material: Reversible Silicone or EPDM
  • Pins & Fasteners Material: 300 Series Stainless Steel
  • Springs Material: Stainless Steel
  • Lead Content: Wetted surface contains less than 0.25% lead by weight

Performance

  • Maximum Working Pressure: 175 psi (12.1 bar)
  • Temperature Range: 33°F - 140°F (0.5°C - 60°C)

Certificates & Approvals

  • AWWA C511-97
  • ASSE 1013
  • CSA B64.4
  • UL Classified (OSY)
  • FM Approved (OSY)
  • NSF Certified to NSF/ANSI 61-G
  • Approved by Foundation for Cross-Connection Control and Hydraulic Research at The University of Southern California (FCCCHR-USC)

FAQs

What is the primary function of the Watts 957Z-OSY-FS backflow preventer?

Its primary function is to protect potable water systems from contamination by preventing the reverse flow of liquids caused by backpressure or backsiphonage, particularly in health hazard applications.

How does the integrated flood sensor work?

The flood sensor detects excessive water discharges from the relief valve. When connected with an optional add-on kit, it relays signals to facility personnel for corrective action, helping to prevent flooding and damage.

What are the key materials used in the construction of this backflow preventer?

The housing and sleeve are constructed from 304 (Schedule 40) stainless steel, and it features lead-free bronze test cocks, EPDM/silicone/Buna-N elastomers, and a stainless steel relief valve.

Is this backflow preventer suitable for all installation orientations?

No, this specific model (957Z-OSY-FS) is approved for horizontal Z-pattern installation. Always ensure it is installed according to the flow arrow direction and local codes.

What certifications does the Watts 957Z-OSY-FS carry?

It is approved by AWWA C511-97, ASSE 1013, CSA B64.4, UL Classified, FM Approved, and NSF Certified to NSF/ANSI 61-G. It also meets the lead-free requirements.

Related Products

1 3