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O-S Fitting

Henry Member Posts: 998
The Northern Electric building had a one pipe gravity system for its 8 floors. The heated water would go to the top floor ceiling and spread out along the outside walls. There would be a pipe going down which would have two O-S tee (like monoflow) for each radiator on each floor. Each down main one would connect to a large return going into the boiler room building which was adjacent to the U shaped main building. As it was converted to multi use rental units, I installed Danfoss thermostatic valves on the radiators by moving them 10 inches from the O-S tee.


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    Come on Henry, you're not new here...where are the inside pictures...:)

    There was an error rendering this rich post.

    delta TCanucker
  • Henry
    Henry Member Posts: 998
    I did have a picture of the TY somewhere, but could not find it this morning.
  • delta T
    delta T Member Posts: 884
    I once found on of the 'Unique' valves made by honeywell, Trying to find a pic for it now....we'll see. P.29 in Classic Hydronics.
  • Steamhead
    Steamhead Member Posts: 16,842
    For those who don't remember, Northern Electric was the Canadian manufacturing unit for Bell Telephone, like Western Electric was for AT&T in the U.S. That building is probably built as well as the equipment that was made there. NE morphed into Northern Telecom, which collapsed recently.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,526
    This is why I love you guys.
    Retired and loving it.
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,287

    This is why I love you guys.