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acid in boiler water?

with calibrated litmus paper to see how bad it really is.

Unless you have shares in Mr. Armand Hammer's company, I would not consider baking soda. You will have much more success with lye, which you can get at Safeway. Put enough in to change the pH to a range between 9 and 10.5. More than that and you run the risk of thinning out your copper pipes. Strong bases are use to remove copper fouling from your favorite pea shooter.


  • johnnyzero
    johnnyzero Member Posts: 7

    We were having trouble with hot water temp & pressure, so about 18 months ago I had a buddy do an "acid treatment" on my tankless h/w coil until I had the time/money to replace the coil. He used a hand pump, along with the hose bibs and valves on either side of the coil - like you're supposed to.

    When draining the boiler & system to replace the coil a few months ago, I noticed that the water had a very strong smell - that same acrid smell as the acid he used (muriatic?). It wasn't just a weak acid solution either - when I sucked on the end of a hose to start siphoning out the remaining boiler water, I thought I was gonna die when that crap hit the back of my throat! (Yeah, I know: I shoulda learned my lesson trying to siphon gasoline in the '70's).Anyway, is it possible that the old coil had a pinhole and the acid got into my boiler/system water?

    Needless to say, I flushed out the boiler & system pipes until everything looked & smelled pretty good; and I figured that was that. However, when I opened the boiler drain valve again the other day (to do some other work) the water still stinks like acid. Is there some type of "neutralizer" that I can run thru the system, and then just flush it out with some more water? I know that this acid is pretty caustic, and I wanna make sure it doesn't damage my pipes & boiler over time. I also suspect that the acid solution has a different "specific heat" than plain water.

    Any suggestions will be much appreciated.


  • John Van Hoesen
    John Van Hoesen Member Posts: 91
    Lime or Baking Soda

    Will neatralize the muriatic, however when you do this you're going to release Chlorine (Muriatic Acid is just concentrated hydrochloric acid). So when you introduce the lime or baking soda, you're going to break the HCl bond to produce HCO3- and Cl. Make sure the place is vented. :)

    It would help to know how much HCl is in there, because you could add too much Carbonate to your system and then it will increase any scaling issues. But if you don't know, maybe start off with just a small dose... not sure if any of this helped. :)

    Good luck
  • johnnyzero
    johnnyzero Member Posts: 7

    for the advice. I guess I'll try dissolving some good ol' Arm 'n Hammer in warm water and run that thru, followed by a good flushing. I may also try testing the pH and comparing it to my well water as a reference until it's "right" (my teenage son probably has some litmus paper lying around).

  • Drew_2
    Drew_2 Member Posts: 158

    Use TriSodium Phosphate (TSP) It's used as a cleaner, dissolves in water, is not abrasive and has a high pH.
  • johnnyzero
    johnnyzero Member Posts: 7

    Thanks Drew - I'll try that. I actually have a box of TSP left over from when I refinished an old bath tub a few years ago - I knew it would come in handy someday...

This discussion has been closed.