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Watts Backflow Preventer Repair Kits: First Check Kit, 1 LF919-QT-S-FS - Repair Kits & Parts for Watts Backflow Preventers
WattsRepair Kits & Parts for Watts Backflow Preventers

Watts Backflow Preventer Repair Kits: First Check Kit, 1 LF919-QT-S-FS

The WATTS Backflow Preventer Repair Kits: First Check Kit (SKU 3G-OTH-436792) is a repair kit for Watts backflow preventers, compatible with a 1 in valve size and the RK-919 series. It includes a spring and cover…

SKU 3G-OTH-436792

Also listed as: RK919CK11 · RK 919 CK1 1 · RK-919-CK1-1

Brand
Watts
Item
Backflow Preventer Repair Kits: First Check Kit, 1 LF919-QT-S-FS
Category
Repair Kits & Parts for Watts 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
RK 919-CK1 1
Type
809GC7, 919/LF919
Includes
Spring and Cover O-Ring
Compatible Valve Size
1 in
Compatible with Series
RK-919
Compatible with Mfr. Model No.
LF919

Technical Documents

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

Product Description

The WATTS Backflow Preventer Repair Kits: First Check Kit (SKU 3G-OTH-436792) is a repair kit for Watts backflow preventers, compatible with a 1 in valve size and the RK-919 series. It includes a spring and cover O-ring and is designed for use with the LF919 model (MPN RK 919-CK1 1) and Part No. 809GC7.

Frequently Asked Questions

What is the Watts backflow preventer first check kit used for?

The Watts First Check Kit (MPN RK 919-CK1 1) is used to repair the first check valve in Watts 919 and LF919 series backflow preventers. It restores sealing integrity by replacing the spring and cover O-ring, ensuring the assembly prevents reverse water flow in commercial and residential plumbing systems.

What are the specifications of the Watts 1 LF919-QT-S-FS repair kit?

The Watts 1 LF919-QT-S-FS repair kit (SKU 3G-OTH-436792) is compatible with a 1 in valve size and the RK-919 series. It includes a spring and cover O-ring and is designed for the LF919 model. The manufacturer part number is RK 919-CK1 1. It is also compatible with Part No. 1 LF919-QT-S-FS.

Where to buy Watts backflow preventer repair kits worldwide?

3G Electric supplies Watts backflow preventer repair kits, including the RK 919-CK1 1 first check kit, to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for availability and a quote for your region.

How to install a Watts first check kit in a backflow preventer?

To install the Watts first check kit, isolate the backflow preventer and relieve pressure. Remove the access cover, extract the old spring and cover O-ring, and clean the seating surfaces. Install the new spring and O-ring from the kit, reassemble, and test for proper sealing per local codes.

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 repair kits & parts for watts 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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WATTS Backflow Preventer Repair Kits: Second Check Kit, 1-1/4 LF919-QT-S-FS/1-1/2 LF919-QT-S-FS, 919/LF919, Repair Kit, RK-919 (MPN RK 919-CK2 1-1/4-1-1/2)
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