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Watts Air Vent: One Port, Top Port, 1/2 in MNPT, For Water, Brass Body, 150 psi Max. - Vertical-Discharge Air Vents
WattsVertical-Discharge Air Vents

Watts Air Vent: One Port, Top Port, 1/2 in MNPT, For Water, Brass Body, 150 psi Max.

The Watts FV-4M1-1/2 is a one-port, vertical-discharge air vent with a 1/2 in MNPT top port and a brass body, designed for water systems. It has a maximum pressure of 150 psi and a maximum temperature of 240°F.

SKU 3G-OTH-70058

Also listed as: FV4M112 · FV 4M1 1 2 · FV-4M1-1-2

Brand
Watts
Item
Air Vent: One Port, Top Port, 1/2 in MNPT, For Water, Brass Body, 150 psi Max.
Category
Vertical-Discharge Air Vents
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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
FV-4M1- 1/2
Type
Top Port, For Water, Brass Body, Bottom
MNPT
1/2 in
Max.
150 psi
Product Type
Air Vent

Technical Documents

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

Product Description

The Watts FV-4M1-1/2 is a one-port, vertical-discharge air vent with a 1/2 in MNPT top port and a brass body, designed for water systems. It has a maximum pressure of 150 psi and a maximum temperature of 240°F.

Frequently Asked Questions

What is the Watts FV-4M1-1/2 air vent used for?

The Watts FV-4M1-1/2 is a one-port, vertical-discharge air vent used to automatically release trapped air from water systems, preventing air locks and improving system efficiency. It is commonly installed on hydronic heating and cooling systems, boilers, and piping networks where air accumulation can reduce performance.

What are the specifications of the Watts FV-4M1-1/2 air vent?

The Watts FV-4M1-1/2 has a 1/2 in MNPT top port, a brass body, and a bottom connection. It is rated for water service up to 150 psi maximum pressure and 240°F maximum temperature. The vertical-discharge design vents air upward through the top port.

Where to buy the Watts FV-4M1-1/2 air vent worldwide?

3G Electric supplies the Watts FV-4M1-1/2 air vent to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this genuine Watts part.

How to install the Watts FV-4M1-1/2 air vent?

Install the Watts FV-4M1-1/2 air vent vertically with the bottom port connected to the system high point where air collects. Use thread sealant on the 1/2 in MNPT connection and ensure the vent is oriented so the top port discharges upward. Follow local codes and the manufacturer's instructions for proper operation.

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 vertical-discharge air vents. 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
Air Vent: One Port, Side Port, 1/8 in MNPT, For Water, Brass Body, 125 psi Max., 240°F Max., Bottom (MPN HAV- 1/8)
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Air Vent: One Port, Side Port, 1/8 in MNPT, For Water, Brass Body, 125 psi Max., 240°F Max., Bottom (MPN HAV- 1/8)
Air Vent: One Port, Side Port, 3/4 in MNPT, For Steam, Brass Body, 10 psi Max., 275°F Max., Bottom (MPN 3/4 SVS 3-3/4mipx1/2fip)
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Air Vent: One Port, Side Port, 3/4 in MNPT, For Steam, Brass Body, 10 psi Max., 275°F Max., Bottom (MPN 3/4 SVS 3-3/4mipx1/2fip)
Air Vent: One Port, Side Port, 1/8 in MNPT, For Steam, Brass Body, 10 psi Max., 275°F Max., Side (MPN 1/8 SV)
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Air Vent: One Port, Side Port, 1/8 in MNPT, For Steam, Brass Body, 10 psi Max., 275°F Max., Side (MPN 1/8 SV)
Air Vent: One Port, Side Port, 1/8 in MNPT, For Steam, Brass Body, 1.5 psi Max., 275°F Max., Side (MPN 1/8 SVA)
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Air Vent: One Port, Side Port, 1/8 in MNPT, For Steam, Brass Body, 1.5 psi Max., 275°F Max., Side (MPN 1/8 SVA)
Air Vent: One Port, Top Port, 3/4 in MNPT, For Water, Brass Body, 150 psi Max., 250°F Max., Bottom (MPN 78)
BELL & GOSSETT
Air Vent: One Port, Top Port, 3/4 in MNPT, For Water, Brass Body, 150 psi Max., 250°F Max., Bottom (MPN 78)
Air Vent: One Port, Top Port, 1/8 in FNPT, For Water, Brass Body, 75 psi Max., 240°F Max., Bottom (MPN 113001)
BELL & GOSSETT
Air Vent: One Port, Top Port, 1/8 in FNPT, For Water, Brass Body, 75 psi Max., 240°F Max., Bottom (MPN 113001)

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