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LWCO/auto-fill cutting on frequently

Hi,

We have a residential (house) single pipe steam system where the lwco/auto-fill comes on regularly (every day, several times a day) when the boiler is heating. The water in the sighting glass is always in the lower third of the glass. There don't seem to be any leaks anywhere. Any input? It seems like the boiler shoudln't be filling so often. What woudl be "normal"?

Thanks!

Comments

  • Big Ed_4
    Big Ed_4 Member Posts: 2,712
    No not normal , it indicates there is a leak in the system . Either a steam or condensate leak . Wet condensate returns running under the basement floor will rot . Radiator and main vent can leak . Check the chimney for excess condensation for a leak in the boiler ... Dirty water in the gauge glass indicates steam leak clean water condensate ...
    I have enough experience to know , that I dont know it all
  • RichBNC
    RichBNC Member Posts: 2
    Thanks. How often should the auto fill come on?
  • JohnNY
    JohnNY Member Posts: 3,226
    It's draining out when the boiler is making steam. That's highly likely a leak in the boiler above the water line which most often means a boiler replacement is quickly in order. A residential boiler in most cases should take a gallon or so every 2-3 weeks.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
    Classes
  • RichBNC
    RichBNC Member Posts: 2
    Thanks for the responses. It seems like it has been doing this for years. There is no evident leak in the pipes anywhere or from the boiler itself. How can a steam leak from the boiler/into the chimney be identified?
  • kenlmad
    kenlmad Member Posts: 56
    RichBNC said:

    Thanks for the responses. It seems like it has been doing this for years. There is no evident leak in the pipes anywhere or from the boiler itself. How can a steam leak from the boiler/into the chimney be identified?

    1. It has been said here to be similar to the announcement of a new Pope. You need a cold enough day to view the excessive white "smoke", condensation, leaving the chimney. Or,
    2. Fill the cooled boiler completely with water and observe the underside for drips.