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Steam boiler clogging repeatedly

chad444 Member Posts: 8
I have a residential steam boiler. I get it serviced annually where my plumber cleans out the sight glass and key components, skims the water and puts in the green additive in the water. The issue is that a few days later, the water sight glass is already clogged up and the water level is not able to be monitored properly. Additionally, the other components clog often throughout the year and at times the unit shuts down. It appears that the tank must be full of sediment or rust. This seems to stem from an issue a few years ago when the unit was way overfilled and I think that all of the gunk from my pipes in the upstairs of the house may have washed down into the boiler (my speculation). Bottom line is that I am in an endless cycle of pain here. How can I completely flush out the entire unit and all of the pipes in the spring and basically start new? Is there a process for this or directions somewhere? Appreciate all of your collective support!


  • Fred
    Fred Member Posts: 8,518
    edited April 2018
    If you have a good access point into the boiler, you can use a homemade nozzle/wand to get in there and wash it out. Several have posted pictures of them on here. Also, it may well be that the return lines need to be cleaned out, again, if you have a plug or other access into them, you can snake or flush them out.
  • Kahooli
    Kahooli Member Posts: 112
    What green additive?
  • Fred
    Fred Member Posts: 8,518
    Kahooli said:

    What green additive?

    Good Question! I suspect it's Squick or some other additive that should not be in there.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    The preseason checkup should include:
    1.clean the sight glass.(do it yourself later)
    2.flush out the boiler bottom, through the boiler drain. (Do it yourself later)
    3.check the operation of the low water cutoff. (Do it yourself later)
    4.Clean the burners, and analyse the combustion with a special device.
    At least that’s how a knowledgeable steam pro would do this.
    Drain all the green water out, and then do a skimming, and find another tech to take care of the boiler.—NBC
  • newagedawn
    newagedawn Member Posts: 586
    time for a good skimming, and i wouldnt recommend the green chemical anymore, that chemical is only used to help clean the boiler for skimming not on annual tune ups, but once you skim it that chemical will help in the cleaning, again dont put more in after skimming
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
  • gerry gill
    gerry gill Member Posts: 3,045
    That boiler needs a good wand cleaning and skimming as Fred stated. Even if you have to have the plumber cut and peel the bushing/plug/ etc out of an unused return opening to do it.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • clammy
    clammy Member Posts: 2,766
    The green stuff is surgemaster ,its a ok product but i only use it as a last resort if unable to skim or the boiler has no full port plugs to enable wanding the water side as others have suggested . last resort for me seem to be the normal for the no skim group but w the no skim usually comes the really crappy near boiler piping the 2 go hand and hand like frick and frack.It does supposely have o2 scavengers so its not all bad i guess .peace and good luck
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    What size valve is on the boiler? Installing the biggest full port ball valve would be best for draining out the solidified boiler chemicals from the bottom of the boiler. Is there a floor drain nearby? Use a large hose from the enlarged drain valve over to the floor drain.
    Overfill the boiler to the header, and make it begin to boil. It will be noisy with all the chemicals in it, (one of the reasons not to use them). Open the valve and let the increased pressure from the higher water line push the pieces out. This procedure may have to be repeated several times, maybe with adding more cleaning chemicals to continue to loosen the sludge.
    Next step is skimming the hot water very slowly (dribble), while adding cold to the feed connection. When the water runs cold, you know all the old water has been exchanged.
    Continue the skim until the surface oils no longer show their presence in reflected light on the waters surface, (several hours). Make sure that no more chemicals are added, unless there is a water chemical analysis performed, showing a need for some Rhomaster intervention. Even with bad water, using distilled water would be better, and with a leak-free system, not much ongoing makeup will be needed.
    Finally, clean the sight glass, and pressuretrol/pigtails.—NBC