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

The WATTS Relief Valve (MPN 1 LF174A 100 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, 1 in x 1 in size, constructed from copper silicon alloy, and rated for 150 psi…

SKU 3G-OTH-442478

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

Watts
Manufacturer Part Number
1 LF174A 100 FS
Type
1 in x 1 in, Copper Silicon Alloy
Max. Op Pressure
150 psi
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Relief Valve (MPN 1 LF174A 100 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, 1 in x 1 in size, constructed from copper silicon alloy, and rated for 150 psi maximum operating pressure.

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 to protect water heaters and storage tanks from overpressure. It automatically opens at a set pressure to discharge excess water, preventing system damage. Common in commercial and industrial hot water systems.

What are the specifications of the Watts 1 LF174A 100 FS?

The Watts 1 LF174A 100 FS is a 1 in x 1 in FNPTF x FNPTF relief valve made of copper silicon alloy. It has a maximum operating pressure of 150 psi and complies with ASME Section XIII for hot water service. The valve body is designed for durability in high-temperature systems.

Where to buy Watts relief valves worldwide?

3G Electric supplies Watts relief valves worldwide. As a global industrial 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. We source genuine Watts products for international orders.

How to install a Watts hot water pressure relief valve?

Install the Watts LF174A in the hot water system's tapping, ensuring the valve's pressure rating matches the system. Use thread sealant on the FNPTF connections and orient the discharge piping downward to a safe drain. Never install a shutoff valve between the relief valve and the tank. Follow 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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