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Moving radiator in attic


I used to be very active on this site and received such great help that I have not had to visit here in several years. It's been so long that when I entered my email address (that I've had for many years) it did not recognize it.

So....having said that, we are remodeling our attic and want to relocate an existing radiator from an inside wall to an outside wall. What kind of things should I consider? I will need to add about 22 feet of 2 inch pipe and there will need to be one 45* elbow and one 90 elbow* to connect everything. We have a one pipe system with a Dunkirk 4 section boiler that is about 12 years old. We don't use the attic radiator very often but when we do, it's fully functioning and the boiler was properly size per the EDR to handle it.

Thank you for your input.



  • Jamie Hall
    Jamie Hall Member Posts: 17,682
    Basically the usual one pipe steam stuff: make sure your pitch is adequate. Adding that much pipe you're going to have to go up a couple of inches, though, and support the pipe...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • BobC
    BobC Member Posts: 5,252
    i assume this attic already has a floor, if the ceiling below this pipe extension is not open this could be a fools errand. Every bit of that pipe extension needs to be pitched back to the boiler or that radiator is going to bang or simply not work. That could entail lowering the ceiling or installing soffits to tun that pipe in.

    make sure a good steam man does the job - BO NOT LET A BUILDING CONTRACTOR TOUCH THAT PIPE!

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Cambello
    Cambello Member Posts: 10
    edited September 2018
    Thank You -

    This is a full walk-up attic. The floor is old tongue and groove planks. The rad is in a finished bedroom and we’re gutting/redoing the room and adding a bathroom. I’m not sure why the rad was originally placed on the inside wall when all he rest of the house rads are properly installed. I should also add that the pipe extension will be above the floor level and but will be routed behind new wall construction.

    I will not allow a general contractor to do the work. There is plenty of space to allow for proper pitch.