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Watts Dual Check with Atmospheric Vent: LFNLF-9, 3/8 in Pipe Size, MNPT x FNPT - Continuous Pressure Dual Check Backflow Preventers
WattsContinuous Pressure Dual Check Backflow Preventers

Watts Dual Check with Atmospheric Vent: LFNLF-9, 3/8 in Pipe Size, MNPT x FNPT

The WATTS LFNLF-9 is a continuous pressure dual check backflow preventer, part of the WATTS Dual Check with Atmospheric Vent series. This model features a 3/8-inch pipe size with MNPT x FNPT connections and a 5 gpm…

SKU 3G-OTH-430237

Brand
Watts
Item
Dual Check with Atmospheric Vent: LFNLF-9, 3/8 in Pipe Size, MNPT x FNPT
Category
Continuous Pressure Dual Check Backflow Preventers
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Technical Specifications

Watts
Manufacturer Part Number
LFNLF9
Type
MNPT x FNPT, NPT
Pipe Size
3/8 in
Flow Rate
5 gpm
Connection Type
MNPT x FNPT
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS LFNLF-9 is a continuous pressure dual check backflow preventer, part of the WATTS Dual Check with Atmospheric Vent series. This model features a 3/8-inch pipe size with MNPT x FNPT connections and a 5 gpm flow rate. It is designed to prevent backflow in continuous pressure applications.

Frequently Asked Questions

What is the WATTS LFNLF-9 dual check backflow preventer used for?

The WATTS LFNLF-9 is a continuous pressure dual check backflow preventer with atmospheric vent, used to prevent reverse flow of contaminated water into potable water lines in residential and commercial plumbing systems. It is suitable for applications where continuous pressure is present, such as boiler feed lines and irrigation systems.

What are the specifications of the WATTS LFNLF-9?

The WATTS LFNLF-9 has a 3/8-inch pipe size with MNPT x FNPT connections and a 5 gpm flow rate. It is part of the WATTS Dual Check with Atmospheric Vent series, designed for continuous pressure backflow prevention. The manufacturer part number is LFNLF9.

Where to buy the WATTS LFNLF-9 worldwide?

3G Electric supplies the WATTS LFNLF-9 dual check backflow preventer to customers worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this WATTS backflow preventer.

How to install the WATTS LFNLF-9 dual check backflow preventer?

Install the WATTS LFNLF-9 in a horizontal or vertical position with the flow arrow pointing downstream. Ensure the atmospheric vent is unobstructed and at least 12 inches above the flood level rim. Use pipe thread sealant on the MNPT connections and test the device per local codes after installation.

Used in

Common applications for Watts
Industrial burner gas safety systems — Watts HF2000 filters with GF-series seal kits maintain clean, regulated gas supply to burner pilot and main flame controls
Commercial heating and boiler installations — Modular filter assemblies support preventive maintenance and component replacement without full system shutdown
Process gas delivery pipelines — DN25 through DN125 filter bodies accommodate varying flow rates and inlet pressures across manufacturing and chemical processes
Gas pressure regulation benches — Multi-stage Watts filter platforms integrate with pressure reducers and safety shutoff valves in test and calibration environments
Equipment retrofit and upgrade projects — Available connection sizes and seal kits enable adaptation of newer Watts components into legacy gas control systems
Planned maintenance and spare-parts inventory — Filter seal kits allow facilities to stock consumables in advance, reducing downtime during scheduled gas system servicing

Watts Products

3G Electric supplies Watts continuous pressure dual check backflow preventers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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