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Watts Reduced Pressure Zone Assembly: LF909 Large, with Flood Detection Sensor - Watts RPZ Backflow Preventers
WattsWatts RPZ Backflow Preventers

Watts Reduced Pressure Zone Assembly: LF909 Large, with Flood Detection Sensor

The Watts LF909 Large is a reduced pressure zone (RPZ) backflow preventer from the Watts RPZ Backflow Preventers product type. This assembly features a cast iron body, flange connections, and an NRS gate valve…

SKU 3G-OTH-444376

Also listed as: LF909DNRSFS · LF909 DNRS FS

Brand
Watts
Item
Reduced Pressure Zone Assembly: LF909 Large, with Flood Detection Sensor
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-DNRS-FS
Type
with Flood Detection Sensor, Cast Iron, Flange
Connection Type
Flange
Shut-Off Valve Type
NRS 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 type. This assembly features a cast iron body, flange connections, and an NRS gate valve shut-off valve, and includes a flood detection sensor. The manufacturer part number is LF909-DNRS-FS.

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 includes a flood detection sensor for leak monitoring and is suitable for high-hazard cross-connections.

What are the specifications of the Watts LF909 RPZ backflow preventer?

The Watts LF909 Large features a cast iron body, flange connections, and an NRS gate valve shut-off valve. It includes a flood detection sensor and is identified by MPN LF909-DNRS-FS. This assembly is part of the Watts RPZ Backflow Preventers product type.

Where to buy the Watts LF909 RPZ backflow preventer worldwide?

3G Electric supplies the Watts LF909 RPZ backflow preventer worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time on this Watts RPZ assembly.

How to install a Watts 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 manufacturer guidelines and consult a licensed plumber.

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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