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Orifices and gravity hot-water heat

HeatingHelp Administrator Posts: 650
edited February 2017 in THE MAIN WALL
Orifices and gravity hot-water heat

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  • ARsales1
    ARsales1 Member Posts: 13
    I thought I was the only stupid one in the room. I feel like it now looking back at some of those older homes where I never figured out about the orifice and suffered grief.

    Thanks for sharing your stupidity.

    A Near Stupid Wethead Brother
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,544
    Happy to help! I do stupid with the best of them. ;-)
    Retired and loving it.
  • Henry
    Henry Member Posts: 998
    This is a very large building that used to be the Nortern Electric plant. 8 plus floors and is a one pipe gravity system. It had a power plant that had 4 mains going to the top floor ceiling. Each one would split in two opposite runs. Each run would feed several feeder pipes that went down to a similare setup in the basement. At each floor were two special 'Y' one would point down the other up which would feed a large cast iron radiator. Inlet into the top of the radiator and return from the bottom of the radiator into the single pipe.

  • jumper
    jumper Member Posts: 2,285
    Gravity works for more than three floors with overhead distribution,as Henry points out. What I don't understand is why so many of these Cadillac systems were one pipe? Water must be pretty tempered by the time it reaches first floor.