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Ghost flow mystery

rattmoy Member Posts: 5
edited November 2021 in Radiant Heating
I have a zone that is drawing hot water even when the circulator pump is not running.  The plumbers installed a new circulator which didn’t fix the issue. Next they added new piping to loop back to the radiant mixing block which also didn’t help.  I can’t help but think that there is a problem with the ifc in the new circulator. Any other ideas on why this is happening? I’ve attached a photo which shows the new pump and new piping. Thank you!


  • rattmoy
    rattmoy Member Posts: 5

  • rattmoy
    rattmoy Member Posts: 5

    HVACNUT Member Posts: 5,864
    Slab leak?
  • Zman
    Zman Member Posts: 7,573
    It looks like you have several circulators working against each other with no hydraulic separation.
    Did this work at one time? If so, What changed?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • mattmia2
    mattmia2 Member Posts: 9,747
    edited November 2021
    In that second picture, what is with that bypass? It looks new.

    So re reading, the problem existed before that? You need to find someone that knows what they are doing. This sounds like they are just trying stuff at random instead of thinking through what is happening and possible.
  • Jon_blaney
    Jon_blaney Member Posts: 318
    TACO says the IFC is included with the circulator. Perhaps the IFC needs to be install when the pump is put in service. Yours may still be in the box.
  • hot_rod
    hot_rod Member Posts: 22,261
    Doesn't seem to be piped right? One sensor removed and display reads oPn?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream