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need help with one pipe steam system,, rookie!

Hi,,,, two family house, new Williamson steam boiler installed,,,, problem: 2nd floor, bathroom and bedroom both leaking dirty water out of air vent, one baseboard on 1st floor leaking water,, bad water hammer at start up and water bubbling inside all three radiator,, these are all radiators for back rooms of house if that helps, front of house radiators working perfect,,,,, all radiators pitched the right way, all valves open, swapped out rad vents on bad radiators and working vents still shooting water so that's not an issue,,,, when boiler installed o have no main vent in basement, and also only have wet return, no dry return,,, pressure in system is good, 0.5 cut in and cut out at 1 , lowest settings possible,,,, any ideas??? Posting pic of boiler and piping hopefully shows enough info,, please look over and share your expert steam thoughts,, thank you !


  • SWEISWEI Posts: 7,356Member
    Oh, my

    looks like a steam boiler installed by someone who's never even seen a steam system, much less worked on one.  Page 11 of the installation manual shows the MINIMUM acceptable near-boiler piping.

    Please tell me you haven't paid the installer in full.
  • lappylappy Posts: 9Member
    not paid in full

    From issues ive said along with pics, what issues do u think im looking at?
  • j a_2j a_2 Posts: 1,796Member
    Oh My x 2

    Open the manual and compare the piping….Not rocket science
  • BobCBobC Posts: 5,018Member
    edited November 2013
    Not even close

    Modern steam boilers must have the near boiler piping done correctly, the old boilers could work with this kind of piping because they had huge steam chests.. Your boiler has no header and no equalizer and that is why the system is misbehaving, call the installer and tell him he has to configure the piping so it looks like the diagram in the installation manual.

    Tell him to install a skim port while he is redoing the boiler piping.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • lappylappy Posts: 9Member
    what a headache

    Guys appreciate the advice,,, so assuming this missing pipe work would definitely b causing these issues I've posted? Second, do I need dry return and main vents installed? So post say yes and some say no?
  • lappylappy Posts: 9Member
    ordering the book

    I've been doing tons of research recently, and ordering book,, figured since I bought this house I might as well become very familiar with steam heating...
  • BobCBobC Posts: 5,018Member
    Dry return/

    It depends on what the rest of the piping in the basement looks like. From your description I assume you have a single pipe steam system (one pipe feeds each radiator). Dry returns are common on two pipe systems; either system needs a way to remove air from the pipes; two pipe systems can have air vents or main traps, single pipe systems should have a main vents near the ends of each steam main

    There are two types of mains you could have.

    A parallel flow system starts high above the boiler and drops gently as it makes it's way around the basement at the end of the main (after the last radiator takeoff) it drops down to the floor into a wet return and back to the boiler - the steam and the condensate both flow in the same direction. If you have more than one steam main be very sure they don't tie together above the new boilers waterline, you old boiler may have had a higher waterline than the new one does

    A counterflow main gently slopes up from the boiler as it works around the basement - the stem flows one way and the water flows the other way. You could have one main that is parallel and the other one that is counterflow bat as close to the ceiling as the main above the boiler is that is not likely.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Jamie HallJamie Hall Posts: 11,470Member
    As a direct answer,

    yes, the bad pipe work around the boiler could be causing a good many, if not most, of your problems, although there may well be other difficulties as well.

    It does sound as though you have a one pipe system (the air vents on the radiators!) -- although it is easy to tell -- if there is only pipe to each radiator, that's what you have.  One pipe systems are a little more sensitive to bad near boiler piping, but all steam systems are sensitive to pipe pitch, as some steam does condense in the mains and risers.  In one pipe systems, the risers and mains and runouts carry all the condensate from the radiators as well as the steam, so it is important that they are pitched correctly.  The book will have a very good description of all of this.

    I don't see insulation on the piping near the boiler.  When you get the near boiler piping straightened out, you should insulate all the pipes which carry steam.  It will help a lot.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
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