Watts Engineering Specification

Product Overview

The Series LF008PCQT is designed for indoor point-of-use applications to prevent backsiphonage of contaminated water back into the potable water supply. Separation of the water supply from the air inlet is accomplished by means of a diaphragm seal. This feature protects against any spillage during start-up or operation. The LF008PCQT features Lead Free* construction to comply with Lead Free* installation requirements.

*The wetted surface of this product contacted by consumable water contains less than 0.25% of lead by weight.

Features

• Standardly supplied with internal polymer coating
• Standardly supplied with Tee handles
• Available less Tee handle with stem wrench flats (for use where space is limited)
• Available in left-handed or right-handed outlet
• Spill-resistant design for indoor use
• Affordable design
• Modular cartridge for ease of service
• Vent uses an O-ring for reliable operation
• Lead Free* cast copper silicon alloy body for durability
• Compact space saving design
• Satin chrome finish available

Installation

The LF008PCQT is designed to be installed at the point-of-use. When factory installed deck/machine mounted on machines or equipment, the critical level of the LF008PCQT shall be not less than 1" (25mm) above the flood rim. If field applied for general plumbing applications, the critical level of the LF008PCQT shall be a minimum of 6" (150mm) above the flood rim.

Specifications

A spill-resistant vacuum breaker (SVB) shall be installed, in accordance with the manufacturer's instructions, as noted on the plans. The valve shall consist of a one-piece modular check and float assembly made of engineered thermoplastic and housed in a Lead Free* cast copper silicon alloy body. Springs shall be stainless steel. The Health Hazard, Anti-Siphon, Spill Resistant Backflow Preventer shall be constructed using Lead Free* materials. Lead Free* Health Hazard, Anti-Siphon, Spill Resistant Backflow Preventer shall comply with state codes and standards, where applicable, requiring reduced lead content. The valve shall be constructed with a molded diaphragm separating the air inlet from the potable water supply to prevent spillage. The valve shall be a Watts Series LF008PCQT.

Materials

• Springs: Stainless steel
• Bonnet: PPO
• Vent Disc: EPDM
• Disc Holder: PPO
• Check Disc: Silicone rubber
• Body: Lead Free* cast copper silicon alloy

Pressure – Temperature

• Temperature Range: 33°F – 180°F (0.5°C – 83°C)
• Maximum Working Pressure: 150psi (10.3 bar)

End Connections

• Female NPT: Ball Valve shutoffs

Capacity

As compiled from documented Foundation for Cross-Connection Control and Hydraulic Research at the University of Southern California lab tests.

Standards

Meets requirements of IAPMO.

Approvals

ASSE 1056, NSF/ANSI 61, B64.1.3

Performance Data

The following charts illustrate typical maximum system flow rates at 7.5 feet per second (2.3 meters per second) for different sizes of the LF008PCQT backflow preventer. These charts show the relationship between pressure drop (ΔP) and flow rate.

3/8" Size

For the 3/8" size, the chart shows that as flow rate increases from 0 gpm (0 lpm) to 5.5 gpm (21 lpm), the pressure drop increases from 0 psi (0 kPa) to approximately 10 psi (69 kPa).

1/2" Size

For the 1/2" size, the chart shows that as flow rate increases from 0 gpm (0 lpm) to 10 gpm (38 lpm), the pressure drop increases from 0 psi (0 kPa) to approximately 14 psi (97 kPa).

3/4" Size

For the 3/4" size, the chart shows that as flow rate increases from 0 gpm (0 lpm) to 30 gpm (114 lpm), the pressure drop increases from 0 psi (0 kPa) to approximately 10 psi (69 kPa).

1" Size

For the 1" size, the chart shows that as flow rate increases from 0 gpm (0 lpm) to 50 gpm (190 lpm), the pressure drop increases from 0 psi (0 kPa) to approximately 10 psi (69 kPa).

Dimensions and Weights

Diagrams and Visuals

Component Diagram

A diagram illustrates the internal components of the LF008PCQT backflow preventer. Key parts labeled include: Hood, Hood Screws (2 required), Vent Spring, Air Bleed Screw, Bleed O-ring (not shown), Test Cock, Shutoff Valve Assembly (2 required), Vent, Bonnet, O-ring, Body, Retainer, and Check Assembly. The diagram shows how these parts are assembled.

Outlet Configuration

Diagrams show the LF008PCQT available in left-handed (LF008PCQT-L) and right-handed (LF008PCQT) outlet configurations.

Typical Installation Diagram

A typical installation diagram shows the LF008PCQT unit connected to a supply hose. It includes an upstream shutoff valve and a test cock. The diagram indicates a minimum clearance of 1 inch (25mm) above the flood rim. Related system components such as a solenoid valve, pressure reducing valve, and a 3/4" hose adapter with strainer washer are also depicted, suggesting potential system integrations.

Notices

NOTICE: The information contained herein is not intended to replace the full product installation and safety information available or the experience of a trained product installer. Users are required to thoroughly read all installation instructions and product safety information before beginning the installation of this product.

NOTICE: Inquire with governing authorities for local installation requirements.

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

Contact Information

USA: T: (978) 689-6066 | Watts.com

Canada: T: (888) 208-8927 | Watts.ca

Latin America: T: (52) 55-4122-0138 | Watts.com

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