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Watts Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 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 1/2 in x 1 1/2 in, Copper Silicon Alloy

The WATTS Relief Valve (MPN 1-1/2 LF174A 150 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, sized 1 1/2 in x 1 1/2 in, constructed from Copper Silicon Alloy, and has an…

SKU 3G-OTH-442517

Brand
Watts
Item
Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 in, Copper Silicon Alloy
Category
ASME Section XIII Hot Water Pressure Relief Valves
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Technical Specifications

Watts
Manufacturer Part Number
1-1/2 LF174A 150 FS
Type
1 1/2 in x 1 1/2 in, Copper Silicon Alloy
Overall Ht
9 1/4 in
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Relief Valve (MPN 1-1/2 LF174A 150 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, sized 1 1/2 in x 1 1/2 in, constructed from Copper Silicon Alloy, and has an overall height of 9 1/4 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, preventing equipment damage and ensuring safe operation.

What are the specifications of the Watts 1-1/2 LF174A 150 FS relief valve?

This Watts relief valve has 1 1/2 inch FNPTF x FNPTF connections, a copper silicon alloy body, and an overall height of 9 1/4 inches. It is rated for ASME Section XIII hot water service. The manufacturer part number is 1-1/2 LF174A 150 FS, and it is designed for pressure relief in hydronic heating systems.

Where to buy the Watts LF174A relief valve worldwide?

3G Electric supplies the Watts LF174A relief valve worldwide. As a global industrial equipment distributor established in 1990, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this valve to any international destination.

How to install a Watts LF174A pressure relief valve?

Install the Watts LF174A in the hot water system's tapping, ensuring the valve body is upright and the discharge piping is directed to a safe drain. Use thread sealant on the FNPTF connections and avoid over-tightening. Never install a shutoff valve between the relief valve and the system. Follow local codes and the manufacturer's instructions for safe operation.

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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