Xylem-Bell & Gossett 113247 DB-3/4 Differential Bypass Valve

The Xylem-Bell & Gossett 113247 is a 3/4-inch differential bypass valve designed for hydronic heating and cooling systems. This automatic valve maintains consistent pressure differential across a hydronic system by opening to bypass excess flow when system pressure rises above the setpoint, protecting equipment and ensuring optimal performance.

Key Features:

• 3/4-inch NPT threaded connections for easy installation
• Automatic operation maintains constant differential pressure
• Protects pumps, control valves, and system components from excessive pressure
• Prevents noise and erosion caused by high velocity flow
• Durable brass construction for long service life
• Factory set differential pressure (adjustable models available)
• Suitable for chilled water, hot water, and glycol solutions

Differential bypass valves are essential components in variable flow hydronic systems, including those with zone valves or modulating control valves. The DB-3/4 automatically diverts flow from the supply to the return line when zone valves close, maintaining proper flow through the circulator and preventing short-cycling or damage to system components.