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Radiant circ

Is it better to have the circ on the supply manifold or return manifold?


  • Ironman
    Ironman Member Posts: 7,181

    The supply. In fact, it must be there in order to draw through the mixing valve, when used.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    VTHVACGUY Member Posts: 2
    edited February 2012
    Radiant circ

    No mixing valve.  120F water, Taco SR504 energizes circ.  Circ now on return
  • kcopp
    kcopp Member Posts: 4,259
    Supply still.

    pumpimg away from the point of no pressure change... aka the expansion tank.
  • NRT_Rob
    NRT_Rob Member Posts: 1,013
    it doesn't really matter that much

    as long as the expansion tank is on the suction side of the pump and is not on the other side of the "load". i.e. if you trace back from the pump suction inlet, you should hit the expansion tank before you hit the radiant loops/radiators or the boiler.

    supply side is slightly better but as long as it's not expansion tank > loop field > pump you'd be ok. If it is expansion > loop field > pump then you're wide open for major air issues.
    Rob Brown
    Designer for Rockport Mechanical
    in beautiful Rockport Maine.
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