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Cleaning Cast Iron Boiler

aircooled81 Member Posts: 205
I have a cast iron boiler with a good amount of mud inside. water blows down brown for a few seconds and back to clear. I looked inside (from the low water cut-out service tee), shined a flash light and its just caked in there.
the lwco btw was filthy too.
Does anyone have any experience with Hydro-Solv 9150, and will this do the trick?
Should I expect more than a few flushes over the coarse of a few days?


  • Steamhead
    Steamhead Member Posts: 16,827
    What make and model is the boiler?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • kcopp
    kcopp Member Posts: 4,431
    Hydosolve is decent stuff. However getting in there w a water wand would be your best bet.
    That is a length of 3/8" copper w/ a hose connection on 1 end and a crimped section on the other end and a number of small holes drilled in the end.

  • SWEI
    SWEI Member Posts: 7,356
    What is the mud made of? Does a magnet attract it?
  • General
    General Member Posts: 120
    Just my opinion, but using chemicals that were designed to protect the boiler and pipes totally destroyed our boiler in 7 short years. Our LWCO also was clogged each year when the guy came to clean the boiler. The best way is to use a wand. There is actually a good video on you tube as to how it is done.
  • aircooled81
    aircooled81 Member Posts: 205
    Peerless 211 cast iron sectional.
    I don't know if the mud is magnetic, and what its made of.
    Id describe it as brown orange to black if that helps? Basically brown and black but when chipped away brownish orange underneath.
    I'll take a peak at the wand video, but i would hate to clean parts well and other parts poorly creating hot spots or damage to sections because one part was cleaner than the other. Id really hate id a large chunk broke loose and i wasnt able to get it out.
    Also, when cleaning the lwco, i had to scrape and chip mud out of there, something makes me leary even a pressure washer would have been able to seperate that gunk.
  • aircooled81
    aircooled81 Member Posts: 205
    I'm going to try arm & hammer washing soda first, as this is what peerless recomends. They refrence 1 pound per 800sqft edr. That sounds like a lot, anyone know if that was a typo and supposed to be 1 ounce or something smaller?
  • kcopp
    kcopp Member Posts: 4,431
    not a typo...
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    edited May 2016
    Take a sample of the water in a jar, and see how magnetic the sediment would be.
    If the sediment is predominantly calcium, I don't know whether the washing soda will make much difference. You would need something acidic to dissolve the calcium. Rhomar may have some treatment for this.
    Have a good look on the fireside of the sections to see if there are any signs of leaks which may now be sealed with calcium.
    Maybe filling it with RO water would dissolve the calcium.--NBC