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Losing water in glass pipe on steam boiler

chris39 Member Posts: 1
hello everyone, all you good people!:

I have a Weill-McLean steam boiler, 150,000 BTU . Not sure of date. Bought the house 18 months ago. I am losing water in the glass tube,( it disappears under the glass) during operation. The auto water feed does not click on. When the cycle is done, the water returns as normal. The water is a little brown. Recently, I noticed a pin hole under the boiler, consulted a technician and used a solder powder to plug the hole, just long enough to get thru the winter. It seemed to work but it produced heavy water and very dirty. I flushed the entire system 3 times, each time the auto water feed did the filling with no problems. The water was full, clear, and stayed in the tube to the best of my knowledge during operation.
But I am now getting pings again and the water has gotten brown again but not half as bad as when I used the solder powder.
I am concerned about the loss of water. Can anyone think of some solutions?

Thank you so much!!

Chris 39


  • Fred
    Fred Member Posts: 8,518
    Either the boiler needs to be skimmed as oil may be laying on the surface of the water and the steam bubbles can't effectivly break through the surface and pushes the water out into the wet returns.
    Another reason is the system pressure is too high and that pressure is pushing the water out into the wet returns.
    The Pressuretrol should be set at .5PSI Cut-in and the differential (white wheel inside the Pressuretrol) should be set to "1" for a max cut-out pressure of 1.5PSI. Also, make sure the pigtail (looped pipe that the Pressuretrol is mounted on) is not clogged. If it is, the Pressuretrol can't see the actual system pressure and may allow the pressure to build well beyond what it should be.
  • 1Matthias
    1Matthias Member Posts: 148
    @chris39 Mind posting a few photos of the near-boiler piping and the pressuretrol? The pressuretrol is a small grey metal box with a scale on the front, usually mounted near the top front of the boiler. The pointer on the scale should be set to ".5 PSI".
  • Jamie Hall
    Jamie Hall Member Posts: 17,085
    Ah... there should be a low water cutoff, and if the water is really dropping below the bottom of the glass and the cutoff is working, it should shut off the burner and not allow it to fire again until the water is back in the sight glass.

    Please check and make sure this is happening... the low water cutoff is, in my humble opinion, the single most important safety control on a steam boiler.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Big Ed_4
    Big Ed_4 Member Posts: 1,775
    I agree check the low water cut off ... When I meet a new steam home owner and run through the system with them ... Because it's a hands on system ... I add .. If you have no heat in the home and you walk down the basement stairs and it's 100* down there ... Shut the switch to the unit and don't touch anything but the switch , Then get out of the house for 24 hours and come back with a tech ... There is no water in the boiler and its dry firing ... Any water added to the boiler at this state is ex-steam-ly dangerous...
    I have enough experience to know , that I dont know it all
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,429
    Sounds like you need a steam pro. Where are you located?
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems