Submittal Sheet

ManualsBrandsWatts ManualsBackflow Preventers4" 757 Double Check Valve Assembly (OSY)

For Non-Health Hazard Applications

ES-757Na

Job Name

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Contractor

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Job Location

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Approval

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Engineer

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Contractor’s P.O. No.

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Approval

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Representative

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Series 757Na

Double Check Valve Assemblies

Sizes: 2

⁄2" – 6" (65 – 150mm)

Series 757Na Double Check Valve Assemblies are used to pre-

vent backflow of non-health hazard pollutants that are objection-

able but not toxic, from entering the potable water supply system.

The 757Na may be installed under continuous pressure service

and may be subjected to backpressure and backsiphonage.

Series 757Na consists of two independently operating valves,

two shutoff valves, and four test cocks.

Features

• Extremely compact design

• 70% lighter than traditional designs

• 304 (Schedule 40) stainless steel housing & sleeve

• Groove fittings allow integral pipeline adjustment

• Patented bi-link check provides lowest pressure loss

• Unmatched ease of serviceability

• Available with grooved butterfly valve shutoffs

• Available for N pattern installations

• Replaceable check disc rubber

Specifications

The Double Check Valve Assembly shall consist of two inde-

pendent bi-link check modules within a single housing, sleeve

access port, four test cocks and two drip tight shutoff valves.

Bi-link checks shall be removable and serviceable, without the

use of special tools. The housing shall be constructed of 304

Schedule 40 stainless steel pipe with groove end connections.

Bi-link checks shall have reversible elastomer discs and in oper-

ation shall produce drip tight closure against reverse flow caused

by backpressure or backsiphonage. Assembly shall be a Watts

Regulator Company Series 757Na.

757NaBFG

Watts product specifications in U.S. customary units and metric are approximate and are provided for reference only. For precise measurements,

please contact Watts Technical Service. Watts reserves the right to change or modify product design, construction, specifications, or materials with-

out prior notice and without incurring any obligation to make such changes and modifications on Watts products previously or subsequently sold.

Summary of content (4 pages)

PAGE 1
ES-757Na For Non-Health Hazard Applications Job Name –––––––––––––––––––––––––––––––––––––––––––– Contractor ––––––––––––––––––––––––––––––––––––––––––––– Job Location –––––––––––––––––––––––––––––––––––––––––– Approval – ––––––––––––––––––––––––––––––––––––––––––––– Engineer –––––––––––––––––––––––––––––––––––––––––––––– Contractor’s P.O. No.
PAGE 2
Available Models Materials Suffix: Housing & Sleeve: 304 (Schedule 40) Stainless Steel NRS – non-rising stem resilient seated gate valves Elastomers: EPDM, and Buna-N OSY – UL/FM outside stem and yoke resilient seated gate valves Bi-link Checks: Noryl®, Stainless Steel BFG – Check Discs: Reversible EPDM Test Cocks: Bronze Body Nickel Plated UL/FM grooved gear operated butterfly valves with tamper switch Pins & Fasteners: 300 Series Stainless Steel Springs: Stainless Steel *OSY FxG – Flanged i
PAGE 3
Capacity Series 757Na flow curves as tested by Underwriters Laboratory per UL 1469, 1996. Flow characteristics collected using butterfly shutoff valves * = Rated flow ** = UL Rated flow N - Pattern kPa psi 96 14 83 12 69 10 55 8 41 6 28 4 14 2 0 0 * 0 0 50 190 21⁄2" (65mm) 100 380 7.5 2.3 kPa psi 83 12 69 10 55 8 41 6 28 4 14 2 0 0 150 570 * 200 760 ** 15 4.6 N 250 950 300 1140 ** N 0 0 100 380 7.5 2.3 200 760 300 1140 15 4.
PAGE 4
Backflow Prevention Products ES-757Na 0833 USA: 815 Chestnut St., No. Andover, MA 01845-6098; www.watts.com Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.