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Old Grundfos pump curves

Nathan_6 Member Posts: 40
Does anyone have an old grundfos product guide sitting around that covers the UMC 50-80 115v speed 3? I know it crosses with the UPS40-80/4 but I'm putting together a bid to redo a 30 year old system and I'm trying to get the current flow rate of the old 3/4" polybutylene radiant system. So I can make sure I size the new flat plate and stainless circulator correctly when we separate the non barrier tubing from the rest of the system. I currently get a 6.5 to 7 psi increase across the circulator so that should translate to 15 to 16.5 foot of head.

Any help would be great as my old product guides were purged by mistake. :-(


  • Zman
    Zman Member Posts: 7,573
    Siggy's software can model on both circs. If you know the quantity and approx lengths of the loops as well as the common piping, it would be pretty simple to reverse engineer this.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Steamhead
    Steamhead Member Posts: 16,899
    The Grundfos people should have this info. As usual, their site intentionally hides a phone number, but I found this one for "service and support". Hopefully it doesn't go to India:

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service