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steam systems

my Hvac teacher wants us to find the difference between 1 pipe and 2 pipe systems in steam boilers.  Can anyone help?


  • Dave in QCA
    Dave in QCA Member Posts: 1,785
    Well, The simple answer is

    A one pipe system has one pipe and a two pipe system has two pipes.  In a one pipe system both the steam and the condensate travel in the same pipe.  in a two pipe system, the steam travels in one pipe and the condensate and venting occurs through the other pipe.

    But, that is far too simple and I suspect that your teacher expects you to learn a little more than that, perhaps even understand the systems.   Here is a link to a good publication that shows many basic types of steam systems.  Spend a half hour and read, read, read.  After a while it begins to get interesting!   http://documentlibrary.xylemappliedwater.com/files/2012/07/HS-901A.pdf  

    Hope you get an A in the class!
    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.
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