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Safe distance from steam pipe to wall?

HollyP Member Posts: 3
I recently had some work done to my home.  In the course of the work a plumber replaced a pipe carrying steam to my radiator with copper pipe, and moved the pipe.  This pipe is now 1/8 inch or less from the wall. 

I'm concerned about fire.  Is it safe for the pipe carrying steam to a radiator to be so close to the wall?


  • Jamie Hall
    Jamie Hall Member Posts: 16,323
    Shouldn't be a problem

    as far as temperature or fire goes -- steam pipes max out (for low pressure heating) at about 215 F, just above boiling water.  If it's wallpaper under there, it may dry it out and make it crack or curl, but fire... very doubtful indeed.

    On the other hand, it's going to be a bear to paint either the pipe or the wall without painting both!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Patrick_North
    Patrick_North Member Posts: 249
    Maybe not a fire hazard, but...

    I am NOT a professional, but:

    Was this pipe always copper, or did he replace a section of iron pipe? Depending on the circumstances, I'd be concerned that these sweated fittings won't fare well under the expansion and contraction of repeated steaming/cooling cycles. I can imagine your plumber making the switch because copper is easier for him to work with- that doesn't make it an appropriate application.

    I wouldn't be surprised if over time this pipe discolors the paint on the wall, causes the drywall or plaster to crumble, etc. May not be a fire hazard, but it could still cause damage, if only of an aesthetic variety.

    I gather the previous supply pipe wasn't so close to the wall. I'm curious about what the technician has done that altered this placement, and why. How is the pipe now connected to the radiator? If extra fittings were introduced this could affect performance negatively.

    A picture would be helpful if you can post one. From the sound of it, this could be a less than ideal situation that you can live with, or a case where you should demand the work be redone properly.

    Good luck,

  • HollyP
    HollyP Member Posts: 3
    Thanks for your responses.

    The original pipe appeared to be cast-iron... thick, black, heavy.  It ran from the basement to the second floor, through the back of a closet approximately 6 inches from the exterior wall of the house.  (It is no longer an exterior wall, as a room was added on the other side of the wall.)  We removed the closet, and had to move the pipe closer to the wall.  The pipe itself is boxed in, so I'm not worried about painting or papering behind it.

    The original closet opened into the dining room, but the closet space was taken out of the kitchen.  When we renovated the kitchen we took out the closet.  If we'd left the pipe, it would have been sitting approximately 3 feet from the kitchen wall. 

    I appreciate your feedback.  In a couple of years, I may open up a hole in the box containing the pipe just to see what is happenning back there.
  • Rod
    Rod Posts: 2,067
    Test the System

    Holly- If you haven't already done so, you might want to run your steam system and see if all the radiators that could have been affected by the moving of the pipe are now operating properly. It's much easier to make adjustments now than when the weather turns cold.

    - Rod
  • jpf321
    jpf321 Member Posts: 1,566
    from the sounds of it

    from the sounds of it horizontal runs were also added during the reconfiguration. i will assume this is a 1-pipe system? did he use roughly the same diameter pipe at least? doesn't sound like this was a plumber .. maybe a general home improvement "renovator". 
    1-pipe Homeowner - Queens, NYC

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  • gerry gill
    gerry gill Member Posts: 3,011
    do what Rod says,

    and do it twice..bad pipes always work the first time. (then they fill up with condensate), so test it twice, the second time about an hour or two after the first must work twice to be good.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • HollyP
    HollyP Member Posts: 3
    Will do

    Thanks!  I'll test it this weekend, because there is no time for steam heat like a 100 degree Saturday!
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,492
    100 degrees?

    now may be too hot to make a real test of this system, and what exactly would that test consist off?-nbc
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,192
    The old timers had a 70 degree differential

    provision in their contracts. So that would mean getting the home to 170 degrees to prove it worked so you could get paid. I am glad we do not have to do that now a days. I would make sure the pipe is at least insulated with jacketed 1" thick fiberglass insulation and all ends taped to seal them. Yes folks some plumbers do use copper for steam lines, also some plumbers have no idea what they are doing with steam. If it starts baning this fall Holly let your plumber know and have him replace it with iron as it should be. Also keep an eye open for leaking at the fittings. Leaks that go unrepaired lead to floors that are rotted out and need replaced.
    Cost is what you spend , value is what you get.

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  • steamfitter
    steamfitter Member Posts: 156
    steel pipe, cast iron fittings

    Copper may work, but it's usually not a good idea with steam piping, especially if it's not insulated well. Copper expands more and transfers heat more than steel, so in the middle of a steam main or branch, you are liable to get more condensate in that line and a lot more expansion. People install it because it's easy in tough spots avoiding a black cast iron union that's neede to install most steel pipe repairs, which takes up even more space. It may work fine, but I would test it thoroughly as has been suggested. For future reference, tell your contractor: steel pipe and cast iron fittings please, on any steam piping.
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