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Watts Pressure Relief Valve: MNPT x FNPT, 3/4 in x 3/4 in, Brass - ASME Section XIII Hot Water Pressure Relief Valves
WattsASME Section XIII Hot Water Pressure Relief Valves

Watts Pressure Relief Valve: MNPT x FNPT, 3/4 in x 3/4 in, Brass

The WATTS Pressure Relief Valve (MPN 3/4 3L-150) is an ASME Section XIII hot water pressure relief valve with 3/4 in MNPT x FNPT connections in a brass body, rated for a maximum operating pressure of 150 psi. 3G…

SKU 3G-OTH-442455

Brand
Watts
Item
Pressure Relief Valve: MNPT x FNPT, 3/4 in x 3/4 in, Brass
Category
ASME Section XIII Hot Water Pressure Relief Valves
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Technical Specifications

Watts
Manufacturer Part Number
3/4 3L-150
Type
3/4 in x 3/4 in, Brass
Max. Op Pressure
150 psi
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Pressure Relief Valve (MPN 3/4 3L-150) is an ASME Section XIII hot water pressure relief valve with 3/4 in MNPT x FNPT connections in a brass body, rated for a maximum operating pressure of 150 psi. 3G Electric sources this genuine industrial valve across 14 departments, with specialist expertise in combustion, pumps, and controls to ensure the right solution for your application.

Frequently Asked Questions

What is a Watts pressure relief valve used for?

A Watts pressure relief valve protects hot water heating systems from overpressure. It automatically opens when system pressure exceeds 150 psi, discharging water to prevent equipment damage or rupture. Common in commercial and industrial boiler applications.

What are the specifications of the Watts 3/4 3L-150 pressure relief valve?

The Watts 3/4 3L-150 is an ASME Section XIII hot water pressure relief valve. It has 3/4 inch MNPT x FNPT connections, a brass body, and a maximum operating pressure of 150 psi. It is designed for hot water service only.

Where to buy Watts pressure relief valves worldwide?

3G Electric supplies Watts pressure relief valves worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on the Watts 3/4 3L-150.

How to install a Watts pressure relief valve?

Install the Watts valve in the hot water system discharge piping with the arrow on the body pointing in the flow direction. Use pipe dope on male threads, avoid overtightening, and ensure the discharge pipe terminates in a safe, visible location 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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