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Watts Relief Valve: FNPTF x FNPTF, 1 1/4 in x 1 1/2 in, Iron - 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 1/2 in, Iron

The WATTS Relief Valve (SKU 810MV3) is an ASME Section XIII Hot Water Pressure Relief Valve with FNPTF x FNPTF connections, sized 1 1/4 in x 1 1/2 in in iron, rated for a maximum operating pressure of 75 psi (MPN…

SKU 3G-OTH-442519

Brand
Watts
Item
Relief Valve: FNPTF x FNPTF, 1 1/4 in x 1 1/2 in, Iron
Category
ASME Section XIII Hot Water Pressure Relief Valves
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Technical Specifications

Watts
Manufacturer Part Number
1-1/4 740 050 FS
Type
1 1/4 in x 1 1/2 in, Iron
Max. Op Pressure
75 psi
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Relief Valve (SKU 810MV3) is an ASME Section XIII Hot Water Pressure Relief Valve with FNPTF x FNPTF connections, sized 1 1/4 in x 1 1/2 in in iron, rated for a maximum operating pressure of 75 psi (MPN 1-1/4 740 050 FS).

Frequently Asked Questions

What is the Watts 1-1/4 740 050 FS relief valve used for?

The Watts 1-1/4 740 050 FS 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 opening at a set pressure, preventing equipment damage and ensuring safe operation.

What are the specifications of the Watts 1-1/4 740 050 FS relief valve?

This Watts relief valve has a 1 1/4 in FNPTF inlet and 1 1/2 in FNPTF outlet, with an iron body. Its maximum operating pressure is 75 psi. The manufacturer part number is 1-1/4 740 050 FS, and it is designed for ASME Section XIII hot water pressure relief applications.

Where to buy the Watts 1-1/4 740 050 FS relief valve worldwide?

3G Electric supplies the Watts 1-1/4 740 050 FS relief valve worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and a quote for your region.

How to install a Watts hot water pressure relief valve?

Install the Watts relief valve in the hot water system's tapping, ensuring the inlet is connected to the pressure vessel and the outlet is piped to a safe discharge location. Use thread sealant on the FNPTF connections, and never install a shut-off valve between the valve and the system. Test operation after installation.

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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