1-1/2" Brass Circulator Flange with Ball Valve, Less Drain, Female, Iron Pipe x Iron Pipe

Webstone® 1-1/2" Isolation Flange – Model H-40406 | 4040 Series

The Webstone® H-40406 Isolation Flange offers a professional-grade solution for circulator pump isolation in closed-loop hydronic heating systems. As part of the 4040 Series, this 1-1/2" flange combines a full-port brass ball valve and circulator flange into one compact, forged-brass body—designed to simplify pump service, save installation time, and reduce the risk of leaks.

Purpose-Built for High-Volume Hydronic Applications

Engineered to meet the demands of large residential and commercial heating systems, this isolation flange features slotted bolt holes to accommodate high-velocity pumps and a blowout-proof stem for added operational safety. Its uni-body construction reduces labor by eliminating additional fittings while offering direct compatibility with standard 2-bolt pump flanges.

Key Performance Features

• Forged Brass Body – High-strength, corrosion-resistant construction rated for long-term reliability.
• Full-Port Ball Valve – Maintains maximum system flow with minimal pressure drop.
• Blowout-Proof Stem – Prevents stem ejection under pressure and enhances system safety.
• Slotted Mounting Holes – Allows flexibility when aligning with a wide range of circulator pump bolt patterns.
• Integrated Isolation Functionality – Simplifies pump maintenance and eliminates the need for separate shut-off valves.

Technical Specifications

• Model: H-40406
• Series: 4040 Series
• Nominal Size: 1-1/2 inch
• Connection Type: IPS x Flange
• Pressure Rating: 600 PSI WOG
• Temperature Range: Up to 250°F
• Material: Forged brass with PTFE seat and stem seal
• Warranty: Manufacturer’s Limited Lifetime

Installation Notes

This isolation flange is compatible with standard 2-bolt circulator pumps. The IPS threaded inlet allows secure integration with iron pipe systems. Professional installation is strongly recommended to ensure proper torque on pump bolts and threaded connections, as well as compliance with system pressure and code requirements.

Built for Professional Use

The Webstone H-40406 is trusted by HVAC and plumbing contractors for its combination of rugged construction and jobsite efficiency. Designed to reduce installation time and eliminate unnecessary connections, this component delivers reliable performance in even the most demanding hydronic applications.