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Cleaning steam systems

jrc2905 Member Posts: 98
I see a lot of talk about cleaning steam systems. What is a good way to do the cleaning and how often.


  • Sean O
    Sean O Member Posts: 1
    I can feel your pain

    Since I have become the new lord of the boiler, I have been made aware of "The Seasonal Shutdown" requirement, which the former custodians were apparntly as iggnorant of as I. From what I understand, a seasonal purging of the system will control the scale, rust, and setiment buildup that after years of negligence, would result in system breakdown, if not total failure. I'm the new kid on the boiler block and would appriciate any and all input on the proper maitnance "I" can do to minimize my future pain.
  • E. Holtman
    E. Holtman Member Posts: 15
    me too

    I'm similarly new to this. I do, however, have the benefit of a plumber who knows his steam. He has described the cleaning that we will do after the heating season. Since we haven't already done it, here's what I remember.
    First, with a cold boiler, open up a cleanout or tapping that is near or (best) a little above the water line. Then open the water feeder (valve or manual bypass) and SLOWLY add water. The idea is to get the water line even with the clean out so that oils and crud on the surface can flow out. Nice and slow so that the crud doesn't rise above the clean out (in which case, you'd be dumping clean water from underneath.
    After that, open the boiler low and really let it rip out. And then I think there are chemicals that can be added to loosen crud from the bottom. The skimming is the part that's not as intuitive. Cleaning the returns is another part of the project. Hopefully whoever piped it gave you lots of valves and cleanouts down low.
    If anyone has any other tips, I'd be glad to hear them. My boiler hasn't been serviced for so long that if I end up replacing the wet returns, I won't be surprised. If I can get away with cleaning them, bonus.
    I think I saw an article on the web (by Dan?) about cleaning but it was a bit beyond my limited understanding. It might have been in PM online magazine. Google it.
  • Scott25
    Scott25 Member Posts: 30

    There are chemicals that you can add to the system while it is running that will clean the system. You will have to maintain a certain level of this chemical, but it works great. It gradually removes scaling deposits so they can be removed with blowdowns. The drawback is that it doesnt work overnight.

    The chemical of choice for offline cleaning is a specific acid solution. The boiler is filled and this solution is allowed to circulate. It "eats" the scale deposits off. This method does work "overnight" but it can be hard on your equiptment. After an "acid job" the boiler metals will need to be treated to passify the "new" metal that will be exposed.

    Either of these can be pretty tricky so I would suggest that you get some help or suggestions before you try and tackle this yourself.

    email me if you want, maybe I can help you out.
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