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Pipe Slant

I was just wondering, is there any danger that steam pipes are slanted too much?

I know you have to slant them an inch every few ft but is there a drawback to slanting them too much? If not, why don't they slant them more than necessary to eliminate the possibility of water in the pipes?


  • Dave in QCA
    Dave in QCA Member Posts: 1,777

    Generally speaking, pipes run 2 directions, horizontal or vertical.  The vertical pipes are pitched just about as much as you can get them, 100%.  As you know, they work just fine.

    The horizontal pipes need an adequate pitch to assure drainage of the condensate that will form in the pipe.  As long as the pitch is enough to assure drainage of the condensate, they work just fine too.

    There are additional limitations on that horizontal piping, one being the "A" dimension, which states that the lowest portion of a steam carrying pipe must be 28" higher than the boiler water line.  So going backward from the end of the main, (in a parallel flow system) the elevation is going to continue to climb until it gets to the boiler.  If you have 20' ceilings in your basement, you can put way more pitch that is necessary, if you wanted to.  It wouldn't hurt anything, but it wouldn't help anything either.  Most applications are limited by the A dimension and the height of the basement ceiling.  The horizontal piping must remain between those 2 points.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • Rod
    Rod Posts: 2,067
    Get the Books!

    Hi- If you are interested in finding out about the design end of steam heating, I would recommend you get "The Lost Art of Steam Heating" which is available in the Shop section of this website. I mentioned the book "We Got Steam Heat" to you already. Both these books and a third one are available in a package.


    Read "We Got Steam Heat!! "  first as it gives you the definitions as and explains the terminology. ( I didn't and read "The Lost Art..." first and had to constantly refer to "We Got.."  to figure out what was being said. Afterward I realized I would have comprehended "The Lost Art.... much more easily if I had read  "We Got ..." first.)

    These books are written for the homeowner new to steam.  They are humorous, easy reading.and packed full of diagrams and information. A few evenings of reading will put you "light years" ahead in your understanding of residential steam heating.

    Steam heating is actually very easy to understand once you know the parameters. What you have to learn is that some of the steam parameters defy normal logic. One example I can think of is : "Steam travels faster at low pressure than high pressure".

    I constantly "plug" Dan's books as I know they will be beneficial to others as they have been for me. These books have easily saved me over 100 times their value and are probably one of the best investments I have ever made.

    - Rod
  • TeachMeSteam
    TeachMeSteam Member Posts: 128

    I'lll definitely take a look at them.

This discussion has been closed.