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Grundfos isolation flanges

Gordan Member Posts: 891
Any feedback, good or bad? These are the no-handle, screwdriver operated ones, where the flange piece slips over the back of the valve. The screwdriver operation appeals to me more than having a handle that you wind up having to remove.


  • HDE_2
    HDE_2 Member Posts: 140
    Old Stock

    If you came across the screwdriver slot flange sets, they are old stock.

    Once Webstone and many others introduced isolation flanges kits, some with checks, the ones from Grundfos introduced back in the '80's became obsolete. They were 3X the price and contractors preferred handles.
  • Gordan
    Gordan Member Posts: 891
    Yep, kinda figured

    If I prefer the slot type, any reason not to stock up on them? Being old stock, they're not 3x the price any more...
  • I prefer handles,

    as HDE points-out, but if you can get slotted/allen key type they are OK.

    PS- Use the allen key because over time they will get very hard to turn with the slot. ;-)
  • Slimpickins
    Slimpickins Member Posts: 323
    exercise is good

    With this type of flange set, its always good to exercise (open and close) a few times when you're out doing your annual servicing. This will keep them loose so they won't freeze  in the open position.16
  • Gordan
    Gordan Member Posts: 891
    Ok, handles it is. :-)

    Aesthetic concerns do not trump long-term performance.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    But what about homeowners like me...

    While perhaps I can be trusted to know what the handles are for, and that almost all of them should be full on, how would you prevent an ignorant homeowner from turning them, perhaps in a dangerous way?
  • Gordan
    Gordan Member Posts: 891
    That's easy...

    Just remove the homeowner's hands.

    Or the handles on the valves, if you must...
  • hot_rod
    hot_rod Member Posts: 15,028
    they all seize up

    after time. I've twisted the stem off the handle type also. Generally it's not the valve but the quality of the system fluid, that causes them to seize up.

    A little system cleaner, then a hydronic conditioner helps a bunch. Better for all control valves, zone valves, and pump bearings, etc.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    don't go there

    The shafts will get sticky/seized and the slots will chew out. Go with handles. 
  • World Plumber
    World Plumber Member Posts: 389
    Go wit the handles

    With time the slots and allen hex get stripped out and they become inoperable.
  • D107
    D107 Member Posts: 1,777
    5mm Allen drivers

    Just had a service guy out today and he first used a long screwdriver to exercise the valve, which went OK, but then he found his Allen driver (5mm I think he said). It had a wooden handle attached at right angles to the driver, and then an extension and it moved very easily. What do you call that kind of driver with that handle? And where would you pick up this kind of thing? 5mm sounds more like a European calibration. Don't know if ours were Grundfos--see photo.
This discussion has been closed.