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

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

The WATTS Pressure Relief Valve (MPN 3/4 LF3L-150) is an ASME Section IV hot water pressure relief valve with 3/4 in MNPT x FNPT connections in a copper alloy body, rated for a maximum operating pressure of 125 psi…

SKU 3G-OTH-429365

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

Watts
Manufacturer Part Number
3/4 LF3L-150
Type
3/4 in x 3/4 in, Copper Alloy
Max. Op Pressure
125 psi
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Pressure Relief Valve (MPN 3/4 LF3L-150) is an ASME Section IV hot water pressure relief valve with 3/4 in MNPT x FNPT connections in a copper alloy body, rated for a maximum operating pressure of 125 psi. 3G Electric interprets this demand and delivers the genuine OEM part, backed by specialist expertise across 14 industrial departments — including combustion, pumps, and controls — to ensure you get the right solution, not just a catalog listing.

Frequently Asked Questions

What is the WATTS 3/4 LF3L-150 pressure relief valve used for?

The WATTS 3/4 LF3L-150 is an ASME Section IV hot water pressure relief valve used to protect water heaters and boilers from overpressure. It automatically opens at 125 psi to discharge excess pressure, preventing system damage. Common in commercial and residential hydronic heating systems.

What are the specifications of the WATTS 3/4 LF3L-150?

This WATTS pressure relief valve has a 3/4 in MNPT x 3/4 in FNPT connection, a copper alloy body, and a maximum operating pressure of 125 psi. It is ASME Section IV certified for hot water service. The manufacturer part number is 3/4 LF3L-150.

Where to buy the WATTS 3/4 LF3L-150 worldwide?

3G Electric supplies the WATTS 3/4 LF3L-150 pressure 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 lead time.

How to install a WATTS pressure relief valve?

Install the WATTS valve in the hot water system's tapping, ensuring the discharge pipe is directed to a safe drain. Use thread sealant on the MNPT connection. Do not cap or plug the outlet. Test operation after installation by lifting the lever briefly. Follow local plumbing 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 iv 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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