4 957N-DOSY

Item Number: 0113046
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$15,071.59
Special Order
When Will it Ship: Contact for Lead Time
Estimated transit time: 2 to 5 Business Days

Brand - Watts
  • Size: 4 inch
  • Weight: 249.0 lb
  • Assembly Type: Reduced Pressure Zone (RPZ)
  • Shutoff Valves: Domestic OSY Gate Valves
  • Housing & Sleeve: 304 Stainless Steel
  • Maximum Working Pressure: 175 psi
  • Temperature Range: 33°F - 140°F
  • Connections: Groove couplings
  • Lead Content: Lead Free* (<0.25% lead by weight)
  • Includes flood sensor for discharge detection

Description

The Watts Series 957 4 inch N-pattern Reduced Pressure Zone (RPZ) backflow preventer offers robust protection for potable water systems against contamination from backsiphonage and backpressure. It features a durable 304 stainless steel housing, domestic outside stem and yoke (OSY) gate valves, and groove couplings for easy installation. Approved for horizontal installation, this assembly is designed for health hazard applications, providing reliable performance with a maximum working pressure of 175 psi and an integrated flood sensor to detect excessive discharges. Item number 0113046.

Help Me Connect

Installation Orientation

  • This assembly is approved for horizontal installation only, provided it is installed in accordance with the direction of the flow arrow.

Connections

  • This assembly features groove couplings for ease of installation and pipeline alignment with compatible grooved piping systems.

Drain Line Integration

  • When installing a drain line on Series 957 backflow preventers, use 957AG air gaps. Attach the air gap brackets directly onto the flood sensor for proper function.
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Additional Details

This 4 inch N-pattern Reduced Pressure Zone (RPZ) assembly backflow preventer provides essential protection to the potable water system, preventing contamination from backsiphonage or backpressure in accordance with national plumbing codes. This compact assembly is approved for horizontal installation, provided it is installed in alignment with the flow arrow.

Key Features

  • Features domestic outside stem and yoke (OSY) resilient seated gate valves for reliable shutoff.
  • Constructed with a 304 (Schedule 40) stainless steel housing and sleeve for durability.
  • Utilizes patented torsion spring check modules designed for lowest pressure loss and unmatched ease of serviceability.
  • Includes a bottom-mounted cast stainless steel relief valve.
  • Groove couplings facilitate integral pipeline adjustment and ease of installation.
  • Equipped with a flood sensor on the relief valve to detect excessive water discharges, capable of triggering notifications when activated with an add-on connection kit.
  • Designed for health hazard applications and continuous pressure piping.

Construction Materials

  • Housing & Sleeve: 304 (Schedule 40) stainless steel
  • Elastomers: EPDM, Silicone, and Buna-N
  • Torsion Spring Checks: Noryl®, Stainless Steel
  • Check Discs: Reversible Silicone or EPDM
  • Test Cocks: Lead Free* bronze body
  • Pins & Fasteners: 300 Series Stainless Steel
  • Springs: Stainless steel

Notice: An add-on connection kit is required to activate the flood sensor's communication features. Without it, the sensor acts as a passive component. Watts is not responsible for alert failures due to connectivity issues or improper installation.

Specifications

  • Assembly Type: Reduced Pressure Zone (RPZ) Backflow Preventer
  • Size: 4 inch
  • Pattern: N-Pattern
  • Shutoff Valves: Domestic OSY (Outside Stem and Yoke) Resilient Seated Gate Valves
  • Housing & Sleeve Material: 304 (Schedule 40) Stainless Steel
  • Check Discs Material: Reversible Silicone or EPDM
  • Test Cocks Material: Lead Free* Bronze Body
  • Elastomers: EPDM, Silicone, Buna-N
  • Torsion Spring Checks Material: Noryl®, Stainless Steel
  • Pins & Fasteners Material: 300 Series Stainless Steel
  • Springs Material: Stainless Steel
  • Maximum Working Pressure: 175 psi (12.1 bar)
  • Temperature Range: 33°F - 140°F (0.5°C - 60°C)
  • Lead Content: Wetted surface contains less than 0.25% lead by weight (Lead Free*)

Certificates & Approvals

  • AWWA C511-97
  • ASSE 1013
  • CSA B64.4
  • CULUS Classified (BFG & OSY Only)
  • FM Approved (BFG & OSY Only)
  • NSF Certified to NSF/ANSI 61-G

FAQs

What is the primary purpose of the Watts 4 inch Series 957 backflow preventer?

This backflow preventer is designed to protect potable water systems from contamination due to backsiphonage or backpressure, ensuring compliance with national plumbing codes for health hazard applications.

What type of shutoff valves are included with this assembly?

This assembly is equipped with domestic outside stem and yoke (OSY) resilient seated gate valves, which provide reliable shutoff capability.

What materials are used for the main housing and key internal components?

The housing and sleeve are made from 304 (Schedule 40) stainless steel. Key components like torsion spring checks use Noryl® and stainless steel, while test cocks feature a Lead Free* bronze body.

What are the maximum operating pressure and temperature limits for this device?

The Watts 4 inch Series 957 backflow preventer has a maximum working pressure of 175 psi (12.1 bar) and an operating temperature range of 33°F to 140°F (0.5°C to 60°C).

Does this backflow preventer include a flood sensor?

Yes, it includes a flood sensor on the relief valve to detect excessive water discharges. An add-on connection kit is required to activate its communication features for notifications.

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