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Adding on to existing Monoflo system

KAB_2 Member Posts: 15
Hi gang, I live in a house built quite right circa 1950, Monoflow system works awesome in original house, have radiant in add-on that also works almost as well.   My plan is to heat the underground garage using some left over cast iron baseboard.  My question is this:  I'd like to use a dormant Monoflo circuit  (I've got a bypass on the tee's), it's near the garage that I plan on heating, but I'd like to just run fostapex or something to make it easy.  The rest of the Monoflo system was made by the "Dead Men" and works great and I don't know what having this kind of Mickey Mouse addition will do to the rest of the system.  Anyone do anything like this? Any rules of thumb? Thanks, KAB


  • Snowmelt
    Snowmelt Member Posts: 1,416

    The cost of this project, seems like it won't cost that much to attempt.

    As long as the btu requirements meet the boiler out put, and you have enough baseboard in the garage, make sure the pump is sized to handle the load. I would try it, worse that can go wronge is take the pex back out and cap it off.
  • KAB_2
    KAB_2 Member Posts: 15

    Yes that's what I was thinking. Btus no problem, I just was throwing it out there to make see if I was missing something. I appreciate the input.
    STEAM DOCTOR Member Posts: 2,014

    The pex will have more resistance to flow then the piping installed by the dead men. The result might be no flow through the pex zone. Doesn't hurt to try.
  • JStar
    JStar Member Posts: 2,752

    I would imagine that the distance of piping will lead to the greatest restriction. I would add a small circulator to the supply line to overcome that friction. You just need to calculate the flow vs. head for the circulator.