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Watts Backflow Preventer Repair Kits: First Check Kit, 957-OSY 21/2/957-OSY3/957OSY4 - Repair Kits & Parts for Watts Backflow Preventers
WattsRepair Kits & Parts for Watts Backflow Preventers

Watts Backflow Preventer Repair Kits: First Check Kit, 957-OSY 21/2/957-OSY3/957OSY4

The WATTS Backflow Preventer Repair Kits: First Check Kit (SKU 3G-OTH-436755) is a repair kit for Watts backflow preventers, including a First Check Module. It is compatible with valve sizes 2-1/2 in to 4 in, Series…

SKU 3G-OTH-436755

Also listed as: RK957957RPDACK12124 · RK957 957RPDA CK1 21 2 4 · RK957-957RPDA-CK1-21-2-4

Brand
Watts
Item
Backflow Preventer Repair Kits: First Check Kit, 957-OSY 21/2/957-OSY3/957OSY4
Category
Repair Kits & Parts for Watts Backflow Preventers
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

Watts
Manufacturer Part Number
RK957/957RPDA-CK1-21/2-4
Type
1RCX3/1RCX5/1RCX7, 757/757DCDA, Repair Kit
Includes
First Check Module
Compatible Valve Size
2-1/2 in to 4 in
Compatible with Series
RK-957
Compatible with Mfr. Model No.
757DCDA

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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-436755) is a repair kit for Watts backflow preventers, including a First Check Module. It is compatible with valve sizes 2-1/2 in to 4 in, Series RK-957, and manufacturer model number 757DCDA. The kit is identified by manufacturer part number RK957/957RPDA-CK1-21/2-4 and is compatible with part number 1RCX7.

Frequently Asked Questions

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

This repair kit is used to replace the first check module in Watts 757DCDA and compatible backflow preventers. It helps maintain backflow prevention in commercial and industrial water systems, ensuring cross-connection control and compliance with plumbing codes.

What are the specifications of the Watts RK957/957RPDA-CK1-21/2-4 repair kit?

The kit includes a First Check Module and is compatible with valve sizes 2-1/2 in to 4 in. It works with Watts Series RK-957 and model 757DCDA backflow preventers. The manufacturer part number is RK957/957RPDA-CK1-21/2-4, and it is also compatible with part number 957OSY4.

Where to buy Watts backflow preventer repair kits worldwide?

3G Electric supplies Watts backflow preventer repair kits worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us to source the RK957/957RPDA-CK1-21/2-4 kit for your maintenance needs.

How to install the Watts first check repair kit?

Installation involves shutting off water supply, depressurizing the system, and removing the old first check module from the backflow preventer. Replace it with the new module from the kit, ensuring proper seating and orientation. Reassemble and test per Watts guidelines. Always follow local plumbing 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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