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

The WATTS Pressure Relief Valve (MPN 3/4 M335M2-030) is an ASME Section IV hot water pressure relief valve with a 3/4 in x 3/4 in MNPT x FNPT connection in bronze, rated for a maximum operating pressure of 20 psi. 3G…

SKU 3G-OTH-429304

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

Watts
Manufacturer Part Number
3/4 M335M2-030
Type
3/4 in x 3/4 in, Bronze
Max. Op Pressure
20 psi
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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The WATTS Pressure Relief Valve (MPN 3/4 M335M2-030) is an ASME Section IV hot water pressure relief valve with a 3/4 in x 3/4 in MNPT x FNPT connection in bronze, rated for a maximum operating pressure of 20 psi. 3G Electric interprets this demand and delivers genuine industrial equipment across 14 departments, with specialist depth in combustion, pumps and controls as an authorised distributor for brands including Watts, Schneider, ABB, Siemens, SKF, Festo, Fluke, Interpump and FBR.

Frequently Asked Questions

What is the Watts 3/4 M335M2-030 pressure relief valve used for?

The Watts 3/4 M335M2-030 is an ASME Section IV hot water pressure relief valve used in hydronic heating systems and hot water storage tanks. It automatically opens to relieve excess pressure when the system exceeds 20 psi, preventing equipment damage and ensuring safe operation in residential and commercial boiler applications.

What are the specifications of the Watts 3/4 M335M2-030 pressure relief valve?

The Watts 3/4 M335M2-030 is a bronze pressure relief valve with 3/4 in MNPT x 3/4 in FNPT connections. It has a maximum operating pressure of 20 psi and is ASME Section IV certified for hot water service. The valve is manufactured by Watts under part number 3/4 M335M2-030.

Where to buy the Watts 3/4 M335M2-030 pressure relief valve worldwide?

3G Electric supplies the Watts 3/4 M335M2-030 pressure relief valve to customers worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact our team to place an order or request a quote for international shipping.

How to install the Watts 3/4 M335M2-030 pressure relief valve?

Install the Watts 3/4 M335M2-030 valve in the hot water system discharge piping with the inlet connected to the system and outlet directed to a safe drain. Use thread sealant on the MNPT connections and ensure the valve is oriented vertically. Never install a shutoff valve between the relief valve and the system. 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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