GRUNDFOS - Flange Kit (ALPHA2) (models: UPS15-58FC UPS26-99FC UPS26-150F) bronze flange isolation valve set (threaded)

The Grundfos Bronze Flange Isolation Valve Set (Threaded) is designed for use with ALPHA2, UPS15-58FC, UPS26-99FC, and UPS26-150F circulator pumps. Manufactured from durable lead-free bronze, this threaded flange kit combines pump mounting flanges with integrated full-port isolation ball valves, allowing circulator pumps to be serviced or replaced without draining the entire hydronic system. Ideal for residential and commercial hydronic heating applications, the isolation valve set simplifies maintenance while reducing system downtime. Precision-machined connections, corrosion-resistant bronze construction, and reliable shut-off performance make this flange kit an excellent choice for boilers, radiant heating systems, fan coils, and closed-loop HVAC installations.

Cross References

• Grundfos — 519756 (1" Bronze Threaded Isolation Valve Set)
• Grundfos — 519755 (3/4" Bronze Threaded Isolation Valve Set)
• Grundfos — 519757 (1-1/4" Bronze Threaded Isolation Valve Set)

Usage

The Grundfos Bronze Flange Isolation Valve Set is installed on the suction and discharge sides of compatible Grundfos circulator pumps. The integrated ball valves allow technicians to isolate the circulator from the hydronic loop, enabling pump replacement, cartridge servicing, or maintenance without draining the heating system. These flange kits are commonly used on boilers, radiant floor heating, fan coil systems, heat pumps, geothermal installations, and commercial HVAC piping. The threaded female NPT connections simplify installation while the bronze construction provides long-term corrosion resistance for closed-loop hydronic systems.