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Watts 1/2 in Brass Double Check Backflow Preventer B911 (MPN 1/2 - Watts Double Check Backflow Preventers
WattsWatts Double Check Backflow Preventers

Watts 1/2 in Brass Double Check Backflow Preventer B911 (MPN 1/2

The Watts B911 Boiler Feed Valve with Backflow Preventer is a brass double check backflow preventer with a 1/2 in pipe size and 8.5 in overall length. This model (MPN 1/2 B911T-M3 (W/PRESS)) does not include a…

SKU 3G-OTH-434560

Also listed as: 12B911TM3WPRESS · 1 2 B911T M3 W PRESS · 1-2-B911T-M3-W-PRESS

Brand
Watts
Item
1/2 in Brass Double Check Backflow Preventer B911
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
1/2 B911T-M3 (W/PRESS)
Type
Brass, 911 (MPN 1/2 B911T-M3 (W/PRESS))
Overall Lg
8.5 in
Pipe Size
1/2 in
Shut-Off Valve Type
Shut-Off Valve Not Included

Technical Documents

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

Product Description

The Watts B911 Boiler Feed Valve with Backflow Preventer is a brass double check backflow preventer with a 1/2 in pipe size and 8.5 in overall length. This model (MPN 1/2 B911T-M3 (W/PRESS)) does not include a shut-off valve. 3G Electric interprets customer demand and delivers this genuine industrial component across 14 departments, with specialist depth in combustion, pumps and controls as an authorised distributor.

Frequently Asked Questions

What is the Watts B911 boiler feed valve with backflow preventer used for?

The Watts B911 is a double check backflow preventer designed for boiler feed applications. It prevents contaminated water from flowing back into the potable water supply while allowing safe boiler filling. Common in commercial and industrial heating systems.

What are the specifications of the Watts B911 boiler feed valve?

The Watts B911 has a 1/2 inch pipe size, 8.5 inch overall length, and is made of brass. The manufacturer part number is 1/2 B911T-M3 (W/PRESS). It does not include a shut-off valve. This is a double check backflow preventer for boiler feed lines.

Where to buy the Watts B911 boiler feed valve worldwide?

3G Electric supplies the Watts B911 boiler feed valve worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

How to install the Watts B911 boiler feed valve?

Install the Watts B911 in the boiler feed line with flow direction matching the arrow on the body. Use pipe thread sealant on the 1/2 inch connections. Ensure the backflow preventer is accessible for testing. Follow local plumbing codes and manufacturer guidelines for proper 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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Compatible alternatives & equivalents

Cross-referenced by specification & description
WATTS Boiler Feed Valve w/Backflow Preventer: BD911, FNPT x FNPT, 1/2 in Pipe Size, Bronze, Female (MPN 1/2 BD911T)
Watts
WATTS Boiler Feed Valve w/Backflow Preventer: BD911, FNPT x FNPT, 1/2 in Pipe Size, Bronze, Female (MPN 1/2 BD911T)
WATTS Boiler Feed Valve w/Backflow Preventer: BD911, Sweat x NPT, 1/2 in Pipe Size, Bronze, Female (MPN 1/2 BD911S)
Watts
WATTS Boiler Feed Valve w/Backflow Preventer: BD911, Sweat x NPT, 1/2 in Pipe Size, Bronze, Female (MPN 1/2 BD911S)
WATTS Backflow Preventer: 912HP, 1 in Pipe Size, FNPT x MNPT, 22 gpm Flow Rate, Brass, PTFE, Female (MPN 1 912HP)
Watts
WATTS Backflow Preventer: 912HP, 1 in Pipe Size, FNPT x MNPT, 22 gpm Flow Rate, Brass, PTFE, Female (MPN 1 912HP)
WATTS Backflow Preventer: LF007, 1 1/2 in Pipe Size, FNPT x FNPT, 21.75 in Overall Lg, 33°F – 180°F (MPN 1-1/2 LF007M2-QT-S)
Watts
WATTS Backflow Preventer: LF007, 1 1/2 in Pipe Size, FNPT x FNPT, 21.75 in Overall Lg, 33°F – 180°F (MPN 1-1/2 LF007M2-QT-S)
WATTS Backflow Preventer: 9D, 1/2 in Pipe Size, Sweat x Socket, 18.7 gpm Flow Rate, Brass, Rubber (MPN 1/2 9DS-M3)
Watts
WATTS Backflow Preventer: 9D, 1/2 in Pipe Size, Sweat x Socket, 18.7 gpm Flow Rate, Brass, Rubber (MPN 1/2 9DS-M3)
WATTS Backflow Preventer: 9D, 3/4 in Pipe Size, 18.7 gpm Flow Rate, 4.81 in Overall Lg, Brass (MPN 3/4 9DS-M2)
Watts
WATTS Backflow Preventer: 9D, 3/4 in Pipe Size, 18.7 gpm Flow Rate, 4.81 in Overall Lg, Brass (MPN 3/4 9DS-M2)

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