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underground ciondensate return

aphco Member Posts: 13
I had a call from a potential customer who has a rotten return  under the basement floor.

He wants to kill the line underground and have us run the new piping on top of the floor or hung on the wall.

Sight unseen I have told him that it is probably not a good idea as the Dead Men put it underground for a reason and he could be opening a can of worms by bringing it up above the floor. I explained that it has worked for 80+ years and it was engineered for the circumstances.

 I will be looking at it tomorrow and I promised I would bring something in writing to show him to leave well enough alone. Smart aleck that I am I made the statement before I found anything in writing to back me up. Does anyone know where to find some documentation?

I know that somewhere in his books Dan talked about underground condensate returns, but I am unable to find where he writes about it.

Does anyone have any idea where and what page?. I did a search here and came

up blank. The index doesn't refer to it.


  • Steamhead
    Steamhead Member Posts: 16,732
    Try Chapter 3

    of Lost Art. The bottom line here is that a wet return must be far enough below the waterline to form a proper Hartford Loop, and a dry return must be high enough above the waterline for a decent "A" dimension.

    Depending on where the existing returns are, relative to the waterline, it may be possible to run them above-ground. That would certainly be my choice as long as it doesn't put them where someone would trip over them.

    It's possible that the basement originally had a dirt floor and the returns were originally exposed, and when the present concrete floor was poured they buried the returns.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Jamie Hall
    Jamie Hall Member Posts: 22,941

    -- no surprise.  You may be able to put it above the floor.  Watch those returns and drips -- they must join below the water line, and you must have a decent loop.  I'd be real doubtful about putting it further up -- such as along the wall.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
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