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Steam Main Wet Return Question

Bob Hoff
Bob Hoff Member Posts: 10
What would happen in a Main if the fitting at the bottom of the Wet Return was sufficiently 'crudded-up' as to prevent the condensate from returning to the boiler right away? Sounds to me like the vertical segment of the wet return at the end of my Main #2 is full of water...could such a scenario prevent a Main from functioning?


  • Steamhead (in transit)
    Steamhead (in transit) Member Posts: 6,688
    Yes it could

    and it could also cause banging. Replace the return line.

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  • Bob Hoff
    Bob Hoff Member Posts: 10
    Main not working - Part II

    I am experiencing a familiar situation with my second main. in late February I had the wet returns replaced, the vent valve moved back from directly above the wet return...things worked great for a while. The second main does not get hot at all in the last month. I replaced the main vent since this has solved the problem before (no luck this time). Only thing I can think of is that since replacing the antique with a new boiler at the beginning of the winter we kicked up a bunch of crud in the main piping and it is preventing the air from venting from the main resulting in no heat... Any thoughts?
  • Flush the entrie system.

    Was any skimming done at time of install of the new boiler? If not you more than likely have loosened up some crud in the system.
  • Bob Hoff
    Bob Hoff Member Posts: 10
    Steam Main Wet Return Question

    The installer put an additive in the boiler about a week after the boiler was installed. Since then they came back and fixed the header (too low) and replaced the wet returns and vent valves. Was 'skimming' done when the additive was put in and should they have done it again when they did the additional work? The boiler is surging enough to trigger the low water cutoff when the normal water level drops a little. I'm sure I could put an additive in myself if that is all that is required, beyond that I'm guessing I need to get my installer back and flush the entire system. Not sure at this point if I trust this guy anymore...do you think another contractor would be able (or be willing to) complete?
  • Bob Hoff
    Bob Hoff Member Posts: 10
    Steam Main Wet Return Question

    Morris County,NJ
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    clean the boiler after the install

    there is no substitute for proper cleanning of the boiler after the installation [skimming]. can you make a skunk smell better with perfume? boiler additives are only covering the "presence of the skunk". only pure water should be in your boiler at any time. perhaps you should check your installation by comparing what has been done with the mfg's installation instructions, and then you will know if your boiler was installed correctly or not. most likely your waterline is surging with oily water, and maybe still incorrect piping-check the manual.--nbc

    P.S. is this a similar situation ?

  • RobK
    RobK Member Posts: 5
    steam main

    What was the water volume of the old boiler verses the volume of the new boiler and have you changed the Hartford loop location?
  • Had this happen a few months ago

    1 main left the boiler and teed to 2 separate mains at the other end of the basement . 2 separate wet returns . The unclogged side of the return worked fine . But the clogged side filled up with condensate all the way up in the main . Tons of banging and vents pissing out water .
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