4 LF757DCDA-DOSY-GPM

Item Number: 0792280
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$11,513.36
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When Will it Ship: Contact for Lead Time
Estimated transit time: 2 to 5 Business Days

Brand - Watts
  • Size: 4 inch
  • Weight: 285.0 lb
  • Lead Free* construction
  • Housing & Sleeve Material: 304 Stainless Steel
  • Shutoff Valves: Domestic OSY Gate Valves
  • Bypass Meter: Gallons Per Minute
  • Maximum Working Pressure: 175 PSI
  • Installation: Horizontal, Vertical, or N Pattern
  • Approvals: ASSE 1048, CSA B64.5, FM Approved, NSF 372

Description

The Watts 4 inch LF757DCDA Lead Free Double Check Detector Backflow Preventer Assembly is designed to protect potable water systems from non-health hazard pollutants. It is ideal for fire line sprinkler systems, featuring domestic OSY shutoff valves and a gallons per minute metered bypass to detect leaks and unauthorized water use. This compact, lead-free unit offers easy serviceability and minimal pressure loss. Constructed with 304 stainless steel housing, it can be installed horizontally, vertically, or in an N pattern. Approved by ASSE, AWWA, CSA, FM, and NSF. Max pressure 175 PSI, temperature range 33-140°F.

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Connections and Compatibility

  • This 4 inch double check detector assembly features grooved end connections, allowing for integral pipeline adjustment and facilitating connection to existing grooved piping systems.
  • Designed for installation into potable water supply systems to protect against non-health hazard pollutants.
  • Primarily used with fire line sprinkler systems where monitoring of water use is required.
  • May be integrated into systems using grooved butterfly valve shutoffs.
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Additional Details

The Watts Series LF757DCDA Lead Free Double Check Detector Backflow Preventer Assembly, 4 inch with Domestic OSY Shutoff Valves and a gallons/minute meter, is designed to prevent the backflow of non-health hazard pollutants into the potable water supply system.

It is primarily used in fire line sprinkler systems where monitoring for unauthorized water use is necessary, and for cross-connections involving non-health hazards such as fire protection systems and other service line contaminants.

Key Features

  • Lead Free* construction ensures the wetted surface contains less than 0.25% lead by weight.
  • Extremely compact design, up to 70% lighter than traditional models.
  • Durable 304 Schedule 40 stainless steel housing and sleeve.
  • Groove fittings allow for integral pipeline adjustment.
  • Unique tri-link spring check design provides the lowest pressure loss.
  • Unmatched ease of serviceability without special tools.
  • Available with grooved butterfly valve shutoffs.
  • Can be installed in horizontal, vertical, or N pattern orientations.
  • Equipped with a gallons per minute metered bypass to detect underground leaks and unauthorized water use.
  • Features reversible elastomer check discs and four test cocks.

NOTICE: The information provided is not a substitute for full product installation and safety information. You are required to thoroughly read all installation instructions and product safety information before installing this product. Inquire with governing authorities for local installation requirements.

Specifications

General

  • Series: LF757DCDA
  • Size: 4 inch
  • Construction: Lead Free*
  • Housing & Sleeve Material: 304 (Schedule 40) Stainless Steel
  • Test Cock Body Material: Lead Free* Bronze
  • Tri-link Checks Material: Noryl®, Stainless Steel
  • Check Disc Material: Reversible Silicone or EPDM
  • Pins & Fasteners Material: 300 Series Stainless Steel
  • Springs Material: Stainless Steel
  • Elastomers: EPDM, Silicone, Buna-N
  • Shutoff Valves: Domestic Outside Stem and Yoke (OSY) Resilient Seated Gate Valves
  • Bypass Meter: Registers in Gallons or Cubic Measurement (Gallons Per Minute)

Performance

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

Dimensions & Weight (4 Inch LF757DCDA OSY)

  • Overall Length (A): 33 3/4 inches (857 mm)
  • Height (C OSY Open): 22 3/4 inches (578 mm)
  • Width (D): 4 inches (102 mm)
  • Height to Bypass (P): 9 15/16 inches (252 mm)
  • Weight: 175 lbs (79 kgs)

Certificates & Approvals

  • Approved by Foundation for Cross-Connection Control and Hydraulic Research at The University of Southern California (FCCCHR-USC)
  • AWWA C510-97
  • ASSE 1048
  • CSA B64.5
  • cULus Classified
  • FM Approved (for OSY)
  • NSF Certified to NSF/ANSI 372

FAQs

What is the primary purpose of the Watts LF757DCDA backflow preventer?

The Watts LF757DCDA backflow preventer is designed to prevent the backflow of non-health hazard pollutants from entering the potable water supply system. It is commonly used on fire line sprinkler systems to monitor for unauthorized water usage.

What is the "Lead Free*" construction, and why is it important?

"Lead Free*" construction means the wetted surfaces of the product contain less than 0.25% lead by weight. This is important for maintaining the quality of consumable water in the potable water supply system.

What type of shutoff valves does this assembly include?

This specific Watts LF757DCDA assembly includes domestic Outside Stem and Yoke (OSY) resilient seated gate valves, which are UL/FM approved.

Can this backflow preventer be installed in any orientation?

Yes, the Watts LF757DCDA can be used for horizontal, vertical, or N pattern installations, offering flexibility for various piping configurations.

How does the bypass assembly function on this unit?

The bypass assembly includes a meter that registers in gallons or cubic measurement. This feature is crucial for detecting underground leaks and monitoring for any unauthorized use of water on the system.

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