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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 150 FS) is an ASME Section XIII hot water pressure relief valve with FNPTF x FNPTF connections, sized 1 in x 1 in in a copper silicon alloy construction, rated for a maximum…

SKU 3G-OTH-442480

Also listed as: 1LF174A150FS · 1-LF174A-150-FS

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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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

Watts
Manufacturer Part Number
1 LF174A 150 FS
Type
1 in x 1 in, Copper Silicon Alloy
Max. Op Pressure
150 psi

Technical Documents

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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

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

Frequently Asked Questions

What is a 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 boilers from overpressure. It automatically opens at 150 psi to discharge excess pressure, preventing system damage. Common in commercial and industrial hydronic heating systems.

What are the specifications of the Watts 1 LF174A 150 FS?

This Watts relief valve has 1 in FNPTF x 1 in FNPTF connections, a copper silicon alloy body, and a maximum operating pressure of 150 psi. It is ASME Section XIII rated for hot water service. The manufacturer part number is 1 LF174A 150 FS.

Where to buy Watts relief valves worldwide?

3G Electric supplies and delivers genuine Watts relief valves, including the LF174A series, to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote on the 1 LF174A 150 FS or other Watts pressure relief valves.

How to install a Watts LF174A relief valve?

Install the Watts LF174A in the hot water system discharge piping with the valve stem vertical. Ensure no shut-off valve is placed between the valve and the system. Pipe the discharge to a safe drain location per local codes. Always follow the manufacturer's installation instructions.

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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Compatible alternatives & equivalents

Cross-referenced by specification & description
WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 100 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 100 FS)
WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 125 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 125 FS)
WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 75 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 1 in x 1 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 1 LF174A 75 FS)
WATTS Relief Valve: FNPTF x FNPTF, 2 in x 2 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 2 LF174A 125 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 2 in x 2 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 2 LF174A 125 FS)
WATTS Relief Valve: FNPTF x FNPTF, 3/4 in x 3/4 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 3/4 LF174A 150 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 3/4 in x 3/4 in, Copper Silicon Alloy, 150 psi Max. Op Pressure (MPN 3/4 LF174A 150 FS)
WATTS Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 in, Copper Silicon Alloy, 9 1/4 in Overall Ht (MPN 1-1/2 LF174A 150 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 in, Copper Silicon Alloy, 9 1/4 in Overall Ht (MPN 1-1/2 LF174A 150 FS)

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WATTS Relief Valve: FNPT x FNPT, 1 in x 1 in, Bronze, 94 psi Max. Op Pressure, 5 3/4 in Overall Ht (MPN 1 174A 125 FS)
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WATTS RELIEF VALVE: NPTF x NPTF, 3/4 in x 3/4 in, Iron, 20 psi Max. Op Pressure, 3 1/2 in Overall Ht (MPN F358553)
WATTS Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 in, Bronze, 150 psi Max. Op Pressure (MPN 1-1/2 174A 150 FS)
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WATTS Relief Valve: FNPTF x FNPTF, 1 1/2 in x 1 1/2 in, Bronze, 150 psi Max. Op Pressure (MPN 1-1/2 174A 150 FS)