GRUNDFOS - Flange Kit (ALPHA2) (models: UPS43-44FC, UPS 43-100F) 1-1/2" cast iron flange set

The Grundfos 539605 Cast Iron Flange Set is a genuine replacement mounting kit designed for Grundfos UPS43-44FC and UPS43-100F flange-mounted circulator pumps. Manufactured from heavy-duty cast iron, this flange set provides a secure threaded connection between the circulator pump and hydronic piping system. The kit includes two cast iron flanges, flange gaskets, mounting bolts, and nuts for a complete installation or pump replacement. Designed for residential, commercial, and light industrial hydronic heating systems, the 539605 flange set offers reliable sealing, long-lasting durability, and compatibility with Grundfos UP43 and UPS43 series pumps used in boilers, radiant heating, and HVAC circulation systems.

Cross References

• Grundfos — 539605
• Grundfos — Flanged Set UP43
• Grundfos — GF40/43 1-1/2" Cast Iron Flange Set

Usage

The Grundfos 539605 flange kit is used to mount compatible Grundfos UP43 and UPS43 series circulator pumps to threaded hydronic piping systems. It creates a secure, leak-resistant connection between the pump and the system piping while allowing the circulator to be removed for maintenance or replacement. This flange set is commonly installed on commercial boiler systems, hydronic heating loops, chilled water systems, radiant heating installations, and HVAC circulation equipment. It is intended for use where standard pump flanges are required and does not incorporate isolation valves.