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Watts Double Check Valve Assembly: LF709, 4 in Pipe Size, Flange x Flange, 52.38 in Overall Lg - Watts Double Check Backflow Preventers
WattsWatts Double Check Backflow Preventers

Watts Double Check Valve Assembly: LF709, 4 in Pipe Size, Flange x Flange, 52.38 in Overall Lg

The Watts LF709 Double Check Valve Assembly (SKU 3G-OTH-434584) is a 4-inch pipe size backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, model LF709-OSY, measures 52.38…

SKU 3G-OTH-434584

Also listed as: LF709OSY · LF709 OSY

Brand
Watts
Item
Double Check Valve Assembly: LF709, 4 in Pipe Size, Flange x Flange, 52.38 in Overall Lg
Category
Watts Double Check Backflow Preventers
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Technical Specifications

Watts
Manufacturer Part Number
LF709-OSY
Type
Flange x Flange, 709
Overall Lg
52.38 in
Pipe Size
4 in
Connection Type
Flange x Flange
Shut-Off Valve Type
OSY Gate Valve

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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Watts LF709 Double Check Valve Assembly (SKU 3G-OTH-434584) is a 4-inch pipe size backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, model LF709-OSY, measures 52.38 inches in overall length and is designed for industrial backflow prevention applications.

Frequently Asked Questions

What is the Watts LF709 Double Check Valve Assembly used for?

The Watts LF709 Double Check Valve Assembly is used for industrial backflow prevention, protecting potable water supplies from contamination due to backpressure or backsiphonage. It is suitable for non-health hazard cross-connections in commercial, irrigation, and industrial systems where continuous water service is required.

What are the specifications of the Watts LF709 Double Check Valve Assembly?

The Watts LF709-OSY has a 4-inch pipe size, flange x flange connections, and an OSY gate valve shut-off. Its overall length is 52.38 inches. The manufacturer part number is LF709-OSY, and it is part of the Watts 709 series double check backflow preventers.

Where to buy the Watts LF709 Double Check Valve Assembly worldwide?

You can source the Watts LF709-OSY Double Check Valve Assembly through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time on this backflow preventer.

How to install the Watts LF709 Double Check Valve Assembly?

Install the Watts LF709-OSY in a horizontal position with adequate clearance for maintenance. Ensure the flange connections are properly aligned and gasketed. The OSY gate valve shut-off should be fully open during operation. Follow local plumbing codes and the manufacturer's instructions for backflow preventer 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 watts double 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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