4 LF866-DOSY-GPM-FS

Item Number: F683166
1 1
$15,392.50
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When Will it Ship: Contact for Lead Time
Estimated transit time: 2 to 5 Business Days

Brand - Febco
  • Size: 4 inch
  • Weight: 324.0 lb
  • Lead Free: Yes
  • Body Material: Ductile Iron
  • Coating: ArmorTek® Epoxy System
  • Shutoff Valves: OS&Y Gate Valves
  • Bypass Meter: 5/8" x 3/4" GPM
  • Flood Sensor: Integrated SentryPlus Alert®
  • Maximum Working Pressure: 175 psi

Description

This 4 inch FEBCO MasterSeries LF866 lead free reduced pressure detector backflow preventer assembly protects potable water systems from high hazard/toxic fluids caused by backpressure and backsiphonage. Its ductile iron body features ArmorTek® coating for superior corrosion resistance and stainless-steel internal components for durability. An integrated SentryPlus Alert® flood sensor detects excessive relief valve discharge. The assembly includes OS&Y shutoff valves and a 5/8" x 3/4" GPM metered bypass for leak detection. It is UL Classified, FM Approved, and ASSE 1047 compliant.

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Flood Sensor Connectivity

  • This backflow preventer features an integrated flood sensor with SentryPlus Alert® technology.
  • An add-on connection kit is required to activate the sensor's communication capabilities.
  • Connection kit options include BMS (Building Management System), cellular communication, or the Sensor Control Monitor.
  • The Sensor Control Monitor enables integration with BAS via RS‑485 Modbus or the Nexa® platform through Wi-Fi.
  • Without a connection kit, the flood sensor is passive and does not communicate alerts.

Water System Connections

  • This assembly is designed for installation on potable water supplies at points of cross-connection to protect against backpressure and backsiphonage.
  • End connections are compliant to ASME B16.1 Class 125 and AWWA Class D Flange standards.
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Additional Details

This 4 inch lead free FEBCO MasterSeries® LF866 Reduced Pressure Zone Detector Assembly is designed to protect potable drinking water systems from backpressure and backsiphonage in high hazard/toxic applications.

It includes an integrated flood sensor with SentryPlus Alert® technology to detect excessive water discharges from the relief valve, signaling potential flooding events.

Construction & Design

  • Features a ductile iron body coated with ArmorTek®, a patented three-part advanced epoxy system, to resist microbial-induced corrosion (MIC) and protect exposed metal surfaces.
  • Incorporates a stainless-steel relief valve seat and stainless-steel check components for maximum performance and durability.
  • Designed with inline serviceable assemblies, requiring no special tools for maintenance.
  • Includes OS&Y resilient wedge gate shutoff valves (UL Classified and FM Approved).
  • Equipped with a bypass line featuring a 5/8 inch x 3/4 inch gallons per minute (GPM) water meter to detect leaks or unauthorized water usage.

Flood Sensor Functionality

  • The integrated flood sensor is designed to detect continuous discharge from the relief valve.
  • An add-on connection kit is required to activate the sensor's communication capabilities (BMS, cellular, or Sensor Control Monitor via RS-485 Modbus/Nexa platform via Wi-Fi).
  • Without the connection kit, the flood sensor functions as a passive component and does not communicate with other devices.

Specifications

General

  • Valve Type: Reduced Pressure Zone Detector Assembly
  • Size: 4 inch
  • Lead Free: Yes (less than 0.25% lead by weight)
  • Flood Detection: Integrated SentryPlus Alert® Flood Sensor

Materials

  • Main Valve Body: Ductile iron Grade 65-45-12
  • Relief Valve Body: Ductile iron Grade 65-45-12
  • Coating: ArmorTek powder coating (internal and external surfaces)
  • Shutoff Valves: OS&Y resilient wedge gate valve
  • Check Seats: Stainless steel
  • Relief Valve Seat: Stainless steel
  • Disc Holder: Stainless steel
  • Elastomer Disc: Silicone
  • Spring: Stainless steel

Performance

  • Maximum Working Pressure: 175 psi (12.1 bar)
  • Minimum Working Pressure: 20 psi (1.4 bar)
  • Hydrostatic Test Pressure: 350 psi (24.1 bar)
  • Hydrostatic Safety Pressure: 700 psi (48.3 bar)
  • Temperature Range: 33°F - 140°F (0.5°C - 60°C)

Bypass Assembly

  • Meter Type: 5/8 inch x 3/4 inch GPM (Gallons Per Minute) Water Meter

Certificates & Approvals

  • Foundation for Cross-Connection Control and Hydraulic Research at The University of Southern California (FCCCHR-USC)
  • ASSE 1047
  • UL Classified (US & Canada)
  • FM Approved
  • IAPMO/CUPC
  • AWWA Standard C511 Compliant
  • End Connections: Compliant to ASME B16.1 Class 125 & AWWA Class D Flange
  • NSF Certified to NSF/ANSI/CAN 61 & 372

FAQs

What type of water systems is this backflow preventer designed for?

This backflow preventer is designed for potable drinking water systems to protect against backpressure and backsiphonage conditions in high hazard/toxic applications, as mandated by Local Governing Water Utility Codes.

How does the integrated flood sensor work?

The integrated flood sensor with SentryPlus Alert® technology detects excessive water discharges from the relief valve. To activate its communication features (like sending alerts), an add-on connection kit is required. Without the kit, the sensor is passive.

What are the connectivity options for the flood sensor?

With an add-on connection kit, the flood sensor can communicate via BMS (Building Management System), cellular communication, or through a Sensor Control Monitor that integrates with BAS via RS-485 Modbus or the Nexa® platform via Wi-Fi.

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

The main valve body and relief valve body are constructed from ductile iron Grade 65-45-12. Internal components like check seats, relief valve seats, and disc holders are stainless steel, while the elastomer disc is silicone. All iron components are coated with ArmorTek® for corrosion resistance.

What is the maximum operating pressure and temperature range for this assembly?

This assembly has a maximum working pressure of 175 psi (12.1 bar) and a temperature range of 33°F to 140°F (0.5°C to 60°C).