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Part of the LF757DCDA Series

Ordering Code: 0124718

UPC: 098268841237

Lead Free: YES

4 In Lead Free Double Check Detector Assembly, Osy Shutoff Valves, Bi-Link Check Valves, Gallons/Minute Meter, N Pattern

This 4 IN lead free double check detector assembly prevents the backflow of pollutants that are objectionable but not toxic, from entering into the potable water supply. It is designed for non-health hazard applications and may be installed under continuous pressure service to protect against both backpressure and backsiphonage. It is used primarily on fire sprinkler lines when it is necessary to monitor unauthorized use of water and includes a gallons per minute meter that measures water flow. This assembly consists of two independently operating bi-link check valves, two shutoff valves, four test cocks, and UL/FM outside stem and yoke resilient seated gate valves. It features a compact stainless steel housing and sleeve that is 70 percent lighter than traditional designs and used for horizontal N pattern installation. The maximum working pressure is 175 PSI (12.06 bar).

Product Features

  • Stainless steel for corrosion resistance
  • 150 pound ANSI/AWWA CL D flanged
  • Gallons per minute meter
  • Outside stem and yoke shutoffs
Backflow Preventer Type Double Check Detector Assembly
Body Finish Stainless Steel
Body Material Stainless Steel
Body Pattern N-Pattern
BrandName Watts
Bypass Yes
Cap And Tether No
Elbow Fitting No
Hazard Protection Level Non Health Hazard
Hot And Harsh Water No
Hydrant Connection No
Inlet Connection Size 4 IN
Inlet Connection Type Flanged Joint
Inlet Shutoff Valve Type Outside Stem And Yoke Gate Valve
Inlet Thread Type Does Not Apply To Product
LeadFree YES
Maximum Temperature-Fahrenheit 140
Maximum Working Pressure-BAR 12.10
Maximum Working Pressure-PSI 175
Meter Type GPM
Minimum Temperature-Fahrenheit 33
ModelNumber LF757NDCDA-OSY-GPMA 4
Outlet Connection Size 4 IN
Outlet Connection Type Flanged Joint
Outlet Shutoff Valve Type Outside Stem And Yoke Gate Valve
Outlet Thread Type Does Not Apply To Product
Part Number 0124718
Polymer Coating No
Pressure Operation Continuous
Protection Type Backpressure and Backsiphonage
Seat Material Engineered Plastic
Series LF757DCDA
Strainer No

Product Accessories