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Limescale Removal

Plumdog_2 Member Posts: 873
Any of you guys got recommendations for dissolving heavy limescale deposits around the bottom of a gas tank type water heater? It seems that "Un-Lime" is NLA. My gut tells me vinegar is going to be too slow. I like to see smoke.  


  • icesailor
    icesailor Member Posts: 7,265

    The "Smoke" is mostly CO2 vapors with acid vapors mixed in when you use acid. .

    My final solution was 40 Proof muriatic acid. That masons use to clean mortar haze from brick work. Before that, I always found that the lime scale was just flakes on the bottom of the tank. When I blow the water (drain) in  the tank with compressed air into the cold water supply, and I had a hose on the drain, once the water level got to the bottom, the swirling air swept the lime flakes out of the drain. Put the drain hose in a 5 gallon bucket and see if it fills with chunks. The air and water combination gives agitation.

    It worked for me.
  • hot_rod
    hot_rod Member Posts: 22,262
    A de -lime kit

    Like they sell for tankless water heaters. It includes a tank and small pump. It may be better to circulate the fluid as opposed to just dumping it in

    I have used Hercules Sizzle for boiler de-lime with excellent result. Most plumbing chemical manufacturers have de-lime products available.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream