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setting dimension B


I am planning to replace my steam boiler of unknown age, in my 125-year old home, mostly to upgrade and change the fuel system.  The system works quite well but the oil burner fire box is collapsing.  I think my best solution is to change everything so the manufacturer will have matched the boiler design to the gas burner system.  I got your book "We Got Steam Heat" from one of the contractors I have invited to bid on my job - good selling point for him.  As part of this project, I am interested in raising the boiler as insurance against ground water flooding.  Raising the boiler can't be done without compressing Dimension B.  Can I add a boiler feed pump as a way to compress dimension B and give me the 6-8" extra vertical space I would need?



  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    worries about "b" and "a" dimension

    keep your new boiler "mechanical free" by using a gravity return, with only a few ounces of pressure, using a vaporstat. a pressuretrol will be supplied with your new boiler, but this is best used as a weight to keep the pages of the instruction manual open for the installers, while they work.

    is flooding a real concern here? if the boiler must be raised, then a drop-header would help to keep the steam dry.--nbc
  • JohnHiggins123
    JohnHiggins123 Member Posts: 2
    setting dimension B

  • Charlie from wmass
    Charlie from wmass Member Posts: 4,322
    There is a good chance

    that raising the boiler will not be an issue if the old boiler was very old. The lower water line in the new boiler may do just fine up in the air a bit. Just watch for the A dimension. The use of a drop header as said will allow for the boiler to be lifted with out creating wet steam.

    Having said all this I must put in the disclaimer having not seen the system I could be all wet. Can you post a photo or two?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    RDSTEAM Member Posts: 134
    do you have

    a two pipe steam system or single pipe?? if you have single pipe steam just make sure your water line is 18" to 28" below to lowest horizontal steam carrying pipe. if you have two pipe you need to remember that you need 30" for EVERY pound on your "b" dimension. so if you do raise your boiler up, make sure that you keep your pressure low enough to keep your dimension correct.
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