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

The WATTS Backflow Preventer Repair Kits: Second Check Kit is a repair kit for Watts backflow preventers, including a second check module. It is compatible with valve sizes 2-1/2 in to 4 in and is designed for use…

SKU 3G-OTH-436716

Also listed as: RK957957RPDACK22124 · RK957 957RPDA CK2 21 2 4 · RK957-957RPDA-CK2-21-2-4

Brand
Watts
Item
Backflow Preventer Repair Kits: Second Check Kit, 957-OSY 21/2/957-OSY3/957OSY4
Category
Repair Kits & Parts for Watts Backflow Preventers
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Technical Specifications

Watts
Manufacturer Part Number
RK957/957RPDA-CK2-21/2-4
Type
1RCX3/1RCX5/1RCX7, 957/957RPDA, Repair Kit
Includes
Second Check Module
Compatible Valve Size
2-1/2 in to 4 in
Compatible with Series
RK-957
Compatible with Mfr. Model No.
957

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

Product Description

The WATTS Backflow Preventer Repair Kits: Second Check Kit is a repair kit for Watts backflow preventers, including a second check module. It is compatible with valve sizes 2-1/2 in to 4 in and is designed for use with Series RK-957 and manufacturer model number 957. The kit's manufacturer part number is RK957/957RPDA-CK2-21/2-4.

Frequently Asked Questions

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

The Watts second check kit is a repair component for backflow preventers, specifically the second check module. It is used to restore proper check-valve function in commercial water systems, preventing reverse flow contamination. This kit fits Watts Series 957 and 957RPDA models with valve sizes 2-1/2 in to 4 in.

What are the specifications of the Watts RK957/957RPDA-CK2-21/2-4 repair kit?

This Watts repair kit includes a second check module and is compatible with valve sizes 2-1/2 in to 4 in. It is designed for Series RK-957 and manufacturer model number 957. The manufacturer part number is RK957/957RPDA-CK2-21/2-4, and it is also compatible with part number 957-OSY 21/2.

Where to buy Watts backflow preventer repair kits worldwide?

3G Electric supplies Watts backflow preventer repair kits, including the RK957/957RPDA-CK2-21/2-4 second check kit, to customers worldwide. We handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this genuine Watts repair component.

How to install a Watts second check module repair kit?

Installation of a Watts second check module kit typically involves depressurizing the system, removing the old check assembly, and replacing it with the new module. Ensure the valve size matches 2-1/2 in to 4 in. Follow standard backflow preventer maintenance procedures and local plumbing codes. Always consult the manufacturer's instructions for your specific model.

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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Compatible alternatives & equivalents

Cross-referenced by specification & description
WATTS Backflow Preventer Repair Kits: First Check Kit, 957-OSY 21/2/957-OSY3/957OSY4, 757/757DCDA, Repair Kit (MPN RK957/957RPDA-CK1-21/2-4)
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WATTS Backflow Preventer Repair Kits: First Check Kit, 957-OSY 21/2/957-OSY3/957OSY4, 757/757DCDA, Repair Kit (MPN RK957/957RPDA-CK1-21/2-4)
WATTS Backflow Preventer Repair Kits: Second Check Kit, 957 OSY 6, 6 in Compatible Valve Size (MPN RK 957/957RPDA-CK2 6)
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WATTS Backflow Preventer Repair Kits: Second Check Kit, 957 OSY 6, 6 in Compatible Valve Size (MPN RK 957/957RPDA-CK2 6)
WATTS Backflow Preventer Repair Kits: Complete Rubber Parts Kit, 957-OSY 21/2/957-OSY3/957OSY4, 957/957RPDA (MPN RK 957/957RPDA-RT 21/2-4)
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WATTS Backflow Preventer Repair Kits: Complete Rubber Parts Kit, 957-OSY 21/2/957-OSY3/957OSY4, 957/957RPDA (MPN RK 957/957RPDA-RT 21/2-4)
WATTS Backflow Preventer Repair Kits: Second Check Kit, 1 LF919-QT-S-FS, 1 in Compatible Valve Size, RK-919 (MPN RK 919-CK2 1)
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WATTS Backflow Preventer Repair Kits: Second Check Kit, 5DMJ4/2 LF009M2-QT-S/2 LF009-QT-FS, 009M2, Repair Kit (MPN RK 009M2-CK2 2)
WATTS Backflow Preventer Repair Kits: Second Check Kit, 3/4 LF919-QT-S-FS, 3/4 in Compatible Valve Size, RK-919 (MPN RK 919-CK2-3/4)
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WATTS Backflow Preventer Repair Kits: Second Check Kit, 3/4 LF919-QT-S-FS, 3/4 in Compatible Valve Size, RK-919 (MPN RK 919-CK2-3/4)

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