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External electrolysis to boiler

I have a 3 year old boiler that is showing signs of corrosion/electrolysis (see photos). What is the best approach to solve this issue?


  • hot_rod
    hot_rod Member Posts: 22,271

    To complete the electrical circuit between dissimilar metals that allow that corrosion, you need an electrolyte

    Probably you have a small leak or seep at that connection

    Also the higher the TDS of the fluid or water in that equation the more potential for electrolysis corrosion . Temperature also accelerates the corrosion residue.

    Think like the battery in your truck, dump the acid, electrolyte, out and you stop the battery's ability to generate electricity.

    Take it all apart, reseal all the threaded connections, corrosion will cease.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream