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Expansion tank leak

We've considered the possibility of a roof line leak. I still woudn't rule it out. But we did have a roofer look at the seal around the pipes that poke out of the roof.

Still, as I said, I wouldn't rule it out. One reason is that there is a little bit of corrosion on the outside of the pipe that leads from the tank to the roof, as if water is coming back into the house along the outside of the pipe. (But this corrosion might just be from our humid, Washington, D.C. summers.)

Could it be that the pipe that vents onto the roof gets clogged with ice on the coldest days and that somehow leads to the problem?

Comments

  • Michael Dawson
    Michael Dawson Member Posts: 3
    Expansion tank leak

    Last winter was the first in our new (old) house. As far as I can tell, we have a gravity hot water heating system. It is an upfeed configuration. Twice last winter, we got a leak from the attic into a second-story bedroom. There was a fair amount of water. It happened on what we remember as the coldest days of the year. I could tell from patch marks on the ceiling that the leak had happened before.

    At first, we thought it might be from an expansion tank in the attic, but I looked and couldn't find one. This summer, I went back into the attic and found the tank -- it had been walled in when someone refinished the attic. It's an old tank. It looks like the ones in the drawings on the Q&A on gravity hot water systems. I can't tell exactly where the leak is coming from, whether it is from the tank itself, where the pipe goes into the tank, or the elbow joint about four inches below the tank.

    I need help:

    1. Is there a place where expansion tanks most commonly leak?

    2. Should I replace the fittings into the tank? Should I Replace the tank? Or what?

    Some heating guys say I should cap it off and put a tank in the basement. But I think that will require the addition of a circulator. I'm also worried about messing with a system that works pretty well -- the house heats quickly and comfortably.

    Any advice would be greatly appreciated. Thanks.
  • Weezbo
    Weezbo Member Posts: 6,232
    dont freak *~/:)

    it may be a leak at the roof line.not the tank.
  • Weezbo
    Weezbo Member Posts: 6,232
    might be condensing

    ice. buy a rubber boot and slip it over the pipe,next time it is leaking and freezing cold,go up and look.if you see water running down the pipe to that rubber boot it likely is some leak above the tank.
  • joe c_3
    joe c_3 Member Posts: 5
    leak

    i have removed several of these tanks, and have one in my inventory of old stuff complete with gage glass. if it is vented through roof it is suposed to extend over several inches to side then down,like a pressure relief valve does. it probally rotted off. the other way ive seen it done .
    is the overfill,pipe that is now venting through your roof,gets returned to the cellar slop sink.you fill systom till water shows up in sink. then you dont have to go to attic to check water level. or run outside to see if water is falling off roof yet?
  • Weezbo
    Weezbo Member Posts: 6,232
    thats true:) dumps right on back to the basement floor :)

  • Michael Dawson
    Michael Dawson Member Posts: 3
    leak

    The vent does go off to the side for severation inches. It doesn't go down, but it does point down the roof towards the gutter, so the end of the pipe is below the elbow where the vertical pipe bends by about an inch or so.

    I think what you're also saying is that I can test the system by adding water until either (1) I see water coming onto the roof from the overflow pipe or (2) I see the leak reappear from the tank or the pipe above the tank or somewhere else. Is that right? If I get water coming onto the roof, but no leak, then the problem may have something to do with water freezing in the overflow pipe or something like that.
  • Weezbo
    Weezbo Member Posts: 6,232
    You smart:)

    > The vent does go off to the side for severation

    > inches. It doesn't go down, but it does point

    > down the roof towards the gutter, so the end of

    > the pipe is below the elbow where the vertical

    > pipe bends by about an inch or so.

    >

    > I think

    > what you're also saying is that I can test the

    > system by adding water until either (1) I see

    > water coming onto the roof from the overflow pipe

    > or (2) I see the leak reappear from the tank or

    > the pipe above the tank or somewhere else. Is

    > that right? If I get water coming onto the roof,

    > but no leak, then the problem may have something

    > to do with water freezing in the overflow pipe or

    > something like that.



  • Weezbo
    Weezbo Member Posts: 6,232
    You smart:)

  • lchmb
    lchmb Member Posts: 2,997
    who wouldnt'

    Who wouldn't like to work with Weezbo? I'd almost be willing to travel to alaska to do it. I said almost!! It get's cold up there!! :)
This discussion has been closed.