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Skimming without a skim port

It has been a nightmare here in providence with this old boiler in the place I am renting. So far we have unclogged both tubes that went to the sight glass, got the pressuretrol to work again, added a working gauge so we know that the pressuretrol is working, unclogged the partial clog that was in the return pipe (yes the return pipe was partial clogged!!!), and now I want to skim it because the water is not the best.

I was thinking because there is not a skim port that I open either the top or bottom tube that goes to the sight glass and just slowly open the water that fills the boiler and let that go for awhile. Does that seem like a good or bad idea.

Oh and thanks to everyone that has given sound advice. I would not have made it this far without you!!!


  • BobCBobC Member Posts: 4,457
    edited November 2013
    Skim or flush?

    Do you see a lot of bouncing in the sight glass that makes you think you have oils in the boiler water? The boiler water might just be dirty. If the waterline appears stable you might try draining and filling the boiler a couple of times till the water appears to be pretty clean.This should be done when the boiler is cold or just warm -n you don't want to be adding a lot of cold water to a hot boiler. When you refill the boiler the last time you want to bring it up to steam to drive off the oxygen in the water.

    To answer your original question you can use the upper gauge glass port to skim from if you think you have oils in the water. If you have a valve at the base of the lower cock you can close the lower gauge glass cock and then open up that valve at the base of the lower cock and then when you SLOWLY add water to the boiler it will come out of the top gauge glass port and down through the glass and out to a bucket. The top port is best because it gives you a chance to get any oils that might be clinging to the boiler walls.

    When your done you might consider adding a steam master tablet to the boiler to keep the water clean if you can figure out how to get it in there.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Dave in QCADave in QCA Member Posts: 1,660
    Fantastic Progress!

    I am impressed with the progress you have made. It sounds like you have corrected all of the critical things that were not working correctly.

    Main vents would be of help too, but I understand that it probably is not likely to happen.

    As far as skimming, that is usually done to clean a new boiler because of the oils that are on the new castings. It winds up floating on the top of the boiler water and causes it to foam. Foam then is pushed up the steam lines and creates all kinds of problems. Skimming is the only way to remove the oils from the surface of the water.

    Since your boiler is not new (understatement of the year), I don't think that skimming is necessarily what you need to do. You did encounter a clogged return pipe and have cleaned it out. I suspect that most of the dirt in the boiler is setting in the lower part of the casting section. I don't know where your fill water goes into the boiler, but if it is on the opposite side as where the drain is, you might try just flushing it with fresh water running in and running out the drain. Make sure the boiler is cold! Or, you may have to fill the boiler then empty it. I think after doing this a few times, it will clean up somewhat.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • SWEISWEI Member Posts: 7,356
    Degunking an old system might be worth considering.
  • JHprovidenceJHprovidence Member Posts: 51
    thanks to all

    I see a couple of drains in my near future. WIth this boiler being somewhere around 80 years old and my landlord seeing the benefit of the steam master tablets or rhomarwater the question is what to do. With it being so very old should we leave it clean, steam master tablets, or rhomarwater?
  • MDNLansingMDNLansing Member Posts: 297

    I skim mine through the low water cut off port. I'm able to slide the LWCO out, and insert a piece of radiator hose. This lets me get far enough away from the boiler for the water to land in a bucket. Works pretty well on my boiler. I was weary of trying to remove a boiler plug to I used an existing opening and it did the trick.

    If the water is real dirty, you might want to try using a wand and brush to clean it before skimming. Skimming is only going to take care of the surface oils, it won't remove dirt and sludge from the bottom.
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