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incremental skimming

rcrit Member Posts: 74
I'm finding it difficult to block out the amount of time necessary to properly skim my new boiler so I've been doing it in several hour increments. I've skimmed it twice now for a total of about 5 hours.

The first time I skimmed I got all kinds of black gunky stuff out at first and since then it is generally clear but still oily. Never mind the sheen, I can smell it.

I skimmed tonight for about 2 hours and while it seemed to really clear up towards the end my sight glass is still surging more than it should.

Am I just wasting my time skimming a little here and there or will I eventually get it clean? I realize I'm probably adding a lot more new water doing it this way.
I'm just a homeowner that has a steam system, take my advice with a few grains of salt.


  • LHthread
    LHthread Member Posts: 7
    Cleaning sludge / helps surging Problems

    Go to Hardware / Paint store...etc

    Pick up a box of TSP = Tri-sodium phosphate.

    This is the same thing as spic and span / or I think it is now called Soilax ? Mix about 3/4 cup in some water to dissolve it, and remove the relief valve carefully (the AKA pop off valve. Pour the solution in the dirty boiler...replace the relief valve.

    With the water level at the normal level...fire the boiler and let it run for a hour.

    Shut off the boiler, and let the water cool for a hour, and then drain carefully.

    Add fresh water..slowly (never to a hot boiler)... make another 3/4 cup + water solution, and ....You know the drill by now.. let it run overnight.

    Next morning...drain and add fresh water as above. See how that happens to adjust the surging. There must be a lot of mud and soil in the boiler water to allow surging.

    The water gets afilm of dirt / oil sludge on top, and actually pushes the water down and out the boiler as the water starts to produce 212º (Steam)..

    Good luck.
  • Rod
    Rod Posts: 2,067

    Hi-  There is no problem with incremental skimming.  The first time I changed some of my piping I didn't think to clean out the new pipe first before installing it and so it took several weeks of multiple skimmings till all the oil and preservative was "steam cleaned " out of the pipes. Saturday mornings were the only time I had available so I skimmed on 5 consecutive Saturday mornings,skimming for about two hours each time.  The best thing I found was to skim very s-l-o-w-l-y.

    If you're hot skimming, you may want to heat the boiler water up close to the boil and then shut off the burner and skim off a couple of gallons and then stop to heat the water up again and then skim again. I found that with the burner on, even though the water wasn't boiling, it  was being stirred up by convention. Shutting the burner off when skimming seemed to settle down the surface of the water and allow the oil to stay on the surface,

    Here's a link to a post on skimming: http://www.heatinghelp.com/forum-thread/138635/Need-help-Putting-off-skimmg

    If you can't get the waterline to start to settle down after several periods of skimming then you might try using the washing soda method detailed in the link. As to adding fresh water - in several of the skimming methods you are expected to drain and refill your boiler several times. This creates no problem as long as you bring the new water to the boil shortly after adding it as this drives off any dissolved oxygen.

    - Rod
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