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Watts Backflow Preventer Repair Kits: Second Check Kit - Repair Kits & Parts for Watts Backflow Preventers
WattsRepair Kits & Parts for Watts Backflow Preventers

Watts Backflow Preventer Repair Kits: Second Check Kit

The Watts Second Check Kit (SKU 3G-OTH-436874) is a repair kit for Watts backflow preventers, containing (2) Cam Check with Check O-Rings. It is compatible with Series RK-774 and Mfr. Model No. 774, and fits valve…

SKU 3G-OTH-436874

Also listed as: RK774774DCDACK22124 · RK774 774DCDA CK2 21 2 4 · RK774-774DCDA-CK2-21-2-4

Brand
Watts
Item
Backflow Preventer Repair Kits: Second Check Kit
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
RK774/774DCDA-CK2-21/2-4
Type
36JC71/36JC72/36JC73/36JC78/36JC79/36JC80
Includes
(2) Cam Check with Check O-Rings
Compatible Valve Size
2-1/2 in to 4 in
Compatible with Series
RK-774
Compatible with Mfr. Model No.
774

Technical Documents

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

Product Description

The Watts Second Check Kit (SKU 3G-OTH-436874) is a repair kit for Watts backflow preventers, containing (2) Cam Check with Check O-Rings. It is compatible with Series RK-774 and Mfr. Model No. 774, and fits valve sizes from 2-1/2 in to 4 in.

Frequently Asked Questions

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

A Watts second check kit is used to repair the second check valve assembly in a backflow preventer, ensuring it prevents reverse water flow and contamination. It is designed for Watts Series 774 models and fits valve sizes from 2-1/2 in to 4 in.

What are the specifications of the Watts RK774/774DCDA-CK2-21/2-4 second check kit?

The Watts second check kit (MPN RK774/774DCDA-CK2-21/2-4) includes (2) Cam Check with Check O-Rings. It is compatible with Series RK-774 and Mfr. Model No. 774, and fits valve sizes from 2-1/2 in to 4 in. It is also compatible with Part No. 774-NRS.

Where to buy Watts backflow preventer repair kits worldwide?

3G Electric supplies Watts backflow preventer repair kits, including the second check kit for Series 774, to customers worldwide. We handle full logistics, customs clearance, and delivery, ensuring you receive the correct Watts parts for your valve size from 2-1/2 in to 4 in.

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

To install a Watts second check kit, first depressurize and isolate the backflow preventer. Remove the access cover and replace the existing second check assembly with the new (2) Cam Check and Check O-Rings from the kit. Reassemble and test per local plumbing codes. Always follow the manufacturer's instructions.

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, 774-NRS/774-NRS/774-NRS/774-OSY/774-OSY/774-OSY (MPN RK774/774DCDA-CK1-21/2-4)
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WATTS Backflow Preventer Repair Kits: First Check Kit, 774-NRS/774-NRS/774-NRS/774-OSY/774-OSY/774-OSY (MPN RK774/774DCDA-CK1-21/2-4)
WATTS Backflow Preventer Repair Kits: Second Check Kit, 774-NRS/774-OSY, 6 in Compatible Valve Size (MPN RK 774/774DCDA-CK2 6)
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WATTS Backflow Preventer Repair Kits: Second Check Kit, 774-NRS/774-OSY, 6 in Compatible Valve Size (MPN RK 774/774DCDA-CK2 6)
WATTS Backflow Preventer Repair Kits: First Check Kit, 774-NRS/774-OSY, 6 in Compatible Valve Size (MPN RK 774/774DCDA-CK1 6)
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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)
WATTS Backflow Preventer Repair Kits: First or Second Check Kit, 36JC68/LF719-QT-S, 719/LF719, RK-LF719 (MPN RK 719-CK4 1-1/4-1-1/2)
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WATTS Backflow Preventer Repair Kits: First or Second Check Kit, 36JC68/LF719-QT-S, 719/LF719, RK-LF719 (MPN RK 719-CK4 1-1/4-1-1/2)
WATTS Backflow Preventer Repair Kits: First or Second Check Kit, LF719-QT-S, 719/LF719, RK-LF719 (MPN RK 719-CK4-1/2)
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WATTS Backflow Preventer Repair Kits: First or Second Check Kit, LF719-QT-S, 719/LF719, RK-LF719 (MPN RK 719-CK4-1/2)

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