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iron and copper


I have a gas boiler with cast iron radiators (hot water). Do to a remodel I am relocated 2 radiadators. I have large iron trunks (2 1/2" I think) with 1" tees for the branches to the radiators. I have removed the old 1" iron feeds & returns and going to replace them with 1" copper. Do I need a dielectic connection where the copper threads into the iron tess? There are other points in the system where iron has been replaced with copper and the 2 materials are directly connected so I assume I am safe following suit. Any opinions?


  • EricAune
    EricAune Member Posts: 432
    Copper should be fine

    I personally would not use a dielectric union.  I have replaced/eliminated so many over my short fifteen years in the business due to corrosion; exactly what they are supposed to prevent.  Some would say to use a cast brass fitting at the transition, this is due to the low corrosion characteristics of brass.  If you have future access to this area then I would be completely comfortable using a wrot (standard) copper fitting.
    "If you don't like change, your going to like irrelevance even less"
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