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Watts LF909-DOSY-FS Reduced Pressure Zone Backflow Preventer - Watts RPZ Backflow Preventers
WattsWatts RPZ Backflow Preventers

Watts LF909-DOSY-FS Reduced Pressure Zone Backflow Preventer

The Watts LF909 Large is a reduced pressure zone (RPZ) backflow preventer from the Watts RPZ Backflow Preventers product line. This model (SKU LF909-DOSY-FS, MPN LF909-DOSY-FS) features a cast iron body with flange…

SKU 3G-OTH-444410

Also listed as: LF909DOSYFS · LF909 DOSY FS

Brand
Watts
Item
LF909-DOSY-FS Reduced Pressure Zone Backflow Preventer
Category
Watts RPZ 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
LF909-DOSY-FS
Type
with Flood Detection Sensor, Cast Iron, Flange
Connection Type
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 LF909 Large is a reduced pressure zone (RPZ) backflow preventer from the Watts RPZ Backflow Preventers product line. This model (SKU LF909-DOSY-FS, MPN LF909-DOSY-FS) features a cast iron body with flange connections and includes an OSY gate valve shut-off valve and a flood detection sensor.

Frequently Asked Questions

What is the Watts LF909 RPZ backflow preventer used for?

The Watts LF909 Reduced Pressure Zone Assembly is used to prevent backflow of contaminated water into potable water supplies in commercial, industrial, and municipal systems. It is ideal for high-hazard applications where cross-connection control is critical, such as irrigation, fire protection, and process water lines.

What are the specifications of the Watts LF909-DOSY-FS?

The Watts LF909-DOSY-FS is a large RPZ backflow preventer with a cast iron body and flange connections. It includes an OSY gate valve shut-off valve and a flood detection sensor. The manufacturer part number is LF909-DOSY-FS, and it is part of the Watts RPZ Backflow Preventers product line.

Where to buy the Watts LF909 RPZ backflow preventer worldwide?

You can source the Watts LF909 RPZ backflow preventer 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 model.

How to install a Watts RPZ backflow preventer with a flood detection sensor?

Install the Watts LF909 in a horizontal position with adequate clearance for testing and maintenance. Ensure the flood detection sensor is wired per local codes and connected to an alarm system. Always follow the manufacturer's instructions and consult a licensed plumber for proper installation and testing.

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 rpz 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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Reduced pressure zone backflow preventer with cast iron body and flange connections. Includes OSY gate valve shut-off and flood detection sensor. Used to protect potable water supplies from backflow contamination in high-hazard cross-connection applications
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This reduced pressure zone backflow preventer features a cast iron body with flange connections and an integrated flood detection sensor for early leak warning. It includes an OSY gate valve shut-off type. Used in commercial, industrial, and municipal water systems to protect potable water supplies from cross-connection contamination in high-hazard fluid categories
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This reduced pressure zone backflow preventer features a cast iron body with flange connections and an integrated flood detection sensor for early leak warning. It includes an OSY gate valve shut-off type. Used in commercial, industrial, and municipal water systems to protect potable water supplies from cross-connection contamination in high-hazard fluid categories
Reduced pressure zone backflow preventer with cast iron body, flange connections, and OSY gate valve shut-off. Includes flood detection sensor for leak monitoring. Used to protect potable water supplies from backflow contamination in high-hazard cross-connections
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