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cast iron in a baseboard loop

Is there any issue with adding two cast iron radiators into a baseboard loop?? I am removing the current baseboard in those two rooms.


  • SuperTech
    SuperTech Member Posts: 1,792
    edited March 2020
    If it's fin tube baseboard then I wouldn't do it. Cast iron radiators and baseboards function differently from fin tube and they usually function with different water temperature.
    Are these two rooms on a separate zone from the rest of the house?
    EBEBRATT-Ed Member Posts: 12,007
    You should put the cast iron on a separate loop
  • bandana_man
    bandana_man Member Posts: 6
    its one loop. what would be the major problem is it the temp difference. is it that the velocity slows?
  • mattmia2
    mattmia2 Member Posts: 5,532
    Different output, wouldn't heat the different rooms evenly. The rooms with the CI radiators would overheat before the rooms with the fin tube heated and the mass of the cast iron would mean those rooms would likely still be radiating heat when the rooms with the fin tube called for heat again. You could possibly do something with a trv and bypass on the cast iron if there were some reason it would be difficult to make a separate loop.
  • flat_twin
    flat_twin Member Posts: 318
    Btu output of the baseboard being removed? Btu output of the cast iron rads you intend to install? Supply water temperature of your boiler?
    HVACNUT Member Posts: 4,594
    edited March 2020

    Do you cook? Think cast iron vs stainless steel skillet. Same flame (BTU output) on both burners at the same time.
    The stainless job will be greased, cooked, cleaned, dried, and put away (no drip dry allowed in my house) while the CI skillet is still heating up.