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Watts Double Check Valve Assembly: LF709, 8 in Pipe Size, Flange x Flange, 75.44 in Overall Lg - Watts Double Check Backflow Preventers
WattsWatts Double Check Backflow Preventers

Watts Double Check Valve Assembly: LF709, 8 in Pipe Size, Flange x Flange, 75.44 in Overall Lg

The Watts LF709 Double Check Valve Assembly (SKU 3G-OTH-434591) is an 8-inch pipe size backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, model LF709-OSY, measures…

SKU 3G-OTH-434591

Also listed as: LF709OSY · LF709 OSY

Brand
Watts
Item
Double Check Valve Assembly: LF709, 8 in Pipe Size, Flange x Flange, 75.44 in Overall Lg
Category
Watts Double Check Backflow Preventers
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

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

Technical Documents

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

Product Description

The Watts LF709 Double Check Valve Assembly (SKU 3G-OTH-434591) is an 8-inch pipe size backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, model LF709-OSY, measures 75.44 inches in overall length.

Frequently Asked Questions

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

The Watts LF709 Double Check Valve Assembly is used to prevent backflow of non-potable water into potable water supplies in commercial, industrial, and municipal systems. It is suitable for low-hazard cross-connections where continuous water pressure is required.

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

The Watts LF709 Double Check Valve Assembly has an 8 in pipe size, flange x flange connections, and an OSY gate valve shut-off. Its overall length is 75.44 in. The manufacturer part number is LF709-OSY. It is designed for backflow prevention in water lines.

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

You can source the Watts LF709 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.

How to install the Watts LF709 Double Check Valve Assembly?

Install the Watts LF709 Double Check Valve Assembly in a horizontal or vertical position with adequate clearance for maintenance. Ensure flange connections are properly aligned and gasketed. Follow local plumbing codes and manufacturer guidelines for testing and commissioning.

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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