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Watts Relief Valve: FNPTF x FNPTF, 1 1/4 in x 1 1/4 in, Copper Silicon Alloy - ASME Section XIII Hot Water Pressure Relief Valves
WattsASME Section XIII Hot Water Pressure Relief Valves

Watts Relief Valve: FNPTF x FNPTF, 1 1/4 in x 1 1/4 in, Copper Silicon Alloy

The WATTS Relief Valve (MPN 1-1/4 LF174A 100 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, sized 1 1/4 in x 1 1/4 in, constructed from copper silicon alloy, and has an…

SKU 3G-OTH-442537

Brand
Watts
Item
Relief Valve: FNPTF x FNPTF, 1 1/4 in x 1 1/4 in, Copper Silicon Alloy
Category
ASME Section XIII Hot Water Pressure Relief Valves
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Technical Specifications

Watts
Manufacturer Part Number
1-1/4 LF174A 100 FS
Type
1 1/4 in x 1 1/4 in, Copper Silicon Alloy
Overall Ht
8 1/2 in
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Relief Valve (MPN 1-1/4 LF174A 100 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, sized 1 1/4 in x 1 1/4 in, constructed from copper silicon alloy, and has an overall height of 8 1/2 in.

Frequently Asked Questions

What is the Watts LF174A relief valve used for?

The Watts LF174A is an ASME Section XIII hot water pressure relief valve used in commercial and industrial hydronic systems. It protects boilers, water heaters, and storage tanks from overpressure by automatically discharging water when pressure exceeds the set limit, ensuring safe operation.

What are the specifications of the Watts 1-1/4 LF174A 100 FS relief valve?

This Watts relief valve has 1 1/4 in FNPTF x 1 1/4 in FNPTF connections, a copper silicon alloy body, and an overall height of 8 1/2 in. It is an ASME Section XIII hot water pressure relief valve with manufacturer part number 1-1/4 LF174A 100 FS.

Where to buy Watts relief valves worldwide?

3G Electric supplies Watts relief valves worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on the Watts LF174A or other models.

How to install a Watts LF174A relief valve?

Install the Watts LF174A in the hot water system's tapping, ensuring the valve body is upright and discharge piping is directed to a safe drain. Use thread sealant on the FNPTF connections and do not cap or plug the outlet. Test operation after installation 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 asme section xiii hot water pressure relief valves. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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