3/4" Brass Circulator Flange with Ball Valve, Less Drain, Sweat

Webstone® 5040 Series 3/4" Isolation Flange with Ball Valve – Model H-50403

The Webstone® H-50403 3/4" Isolation Flange from the 5040 Series integrates a full-port brass ball valve directly into the circulator flange, delivering a streamlined solution for hydronic pump installations. Designed for secure, leak-resistant connections, this isolation flange simplifies service, speeds up installation, and eliminates multiple fittings—reducing potential failure points in the system.

Purpose-Built for Hydronic Efficiency

This unit is ideal for heating professionals looking to minimize downtime during pump replacements or repairs. With a forged brass body, blowout-proof stem, and PTFE seat/seal system, the Webstone isolation flange ensures performance under pressure in both residential and light commercial hydronic applications.

Professional Features

• Forged Brass Construction – Corrosion-resistant and pressure-rated for long service life in closed-loop systems.
• Full-Port Ball Valve – Maintains optimal flow capacity with minimal restriction to circulator output.
• Built-In Pump Isolation – Eliminates the need for separate shut-off valves, reducing labor and material costs.
• Blowout-Proof Stem – Enhances safety by preventing stem ejection under pressure conditions.
• Machined Flange Interface – Ensures proper alignment and compatibility with standard 2-bolt pump flanges.

Technical Specifications

• Nominal Size: 3/4 inch
• Connection Type: Sweat (C) x Flange
• Port Type: Full port
• Pressure Rating: 600 PSI WOG (non-shock)
• Temperature Range: Up to 250°F
• Inlet to Outlet Length: 2-9/16 inches
• Top to Inlet Center: 2-1/16 inches
• Sealing Material: PTFE seat and stem seal

Installation Overview

The H-50403 isolation flange is intended for soldered copper piping and standard circulator pumps. Proper orientation and gasket selection are essential for a secure seal. Installation should be performed by qualified professionals to ensure compliance with local codes and system specifications.

Contractor Advantages

By integrating isolation directly into the flange body, Webstone’s 5040 Series eliminates multiple components, saves up to 45 minutes of labor per installation, and reduces system leak paths. It’s a dependable upgrade for serviceability and long-term system performance.