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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 assembly features a cast iron body with flange connections and includes an OSY gate…

SKU 3G-OTH-444409

Also listed as: LF909DOSYFS · LF909 DOSY FS

Brand
Watts
Item
LF909-DOSY-FS Reduced Pressure Zone Backflow Preventer
Part Number
LF909-DOSY-FS
Category
Watts RPZ Backflow Preventers
Available to Order
Also known as:LF909-DOSY-FSWatts
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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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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 assembly features a cast iron body with flange connections and includes an OSY gate valve shut-off valve and a flood detection sensor, as specified by the manufacturer part number LF909-DOSY-FS.

Frequently Asked Questions

What is the Watts LF909 RPZ backflow preventer used for?

The Watts LF909 Reduced Pressure Zone Assembly is used to protect potable water supplies from backflow contamination in commercial, industrial, and municipal systems. It prevents non-potable water from reversing flow into clean water lines, especially in high-hazard cross-connection applications.

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

The Watts LF909-DOSY-FS is a large reduced pressure zone assembly with a cast iron body and flange connections. It includes an OSY gate valve shut-off valve and a built-in 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 assembly.

How to install a Watts LF909 RPZ backflow preventer?

Install the Watts LF909 RPZ assembly in a horizontal position with adequate clearance for testing and maintenance. Ensure flange connections are properly gasketed and bolted. The flood detection sensor should be wired per local codes. Always follow the manufacturer's installation manual and consult a licensed plumber.

Used in

Common applications for Watts
Commercial plumbing – Watts standard capacity water pressure regulators (3/8 LF 26AB) for stabilizing incoming water pressure
Industrial steam systems – Watts 152A series steam pressure regulators for pressure reduction in process and heating lines
Cross-connection control – Watts 757 double check backflow preventers for commercial and industrial water supply protection
Boiler safety – Watts ASME Section XIII temperature and pressure relief valves for overpressure protection in heating systems
Hydronic heating – Watts CP16 pilot-operated pressure regulators for maintaining consistent pressure in steam or water loops
Water hammer mitigation – Watts LF15M2-A water hammer arrestors for absorbing surges in quick-closing valve applications
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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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