dielectric unions/nipples

Old 01-28-06, 02:34 PM
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dielectric unions/nipples

is there a procedure for installing new valves(brass) into a galvanized system that will eliminate the occurance of rust at the joint? all dielectric unions i have found are for threaded to sweat fittings. i have found one location that offers dielectric nipples, but only in size of w.h. outlets. what am i missing? another question is could the pipe "dope" that i use be the issue, i inspected previous repairs on the galv. system and when "tape" was used i see no rust, but where i used the paste i am noticing rust, whats up with that?
thanks to all for your help
Old 01-28-06, 05:07 PM
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Most brass fittings do not require a dielectric fitting. Something about the brass that does not cause electrolosis as copper does. Your pipe dope may be causing moisture to form at the joints. Teflon does not have any oils or moisture so that may be the reason. Good luck.
DIY sells dielectric nipples in 3/4". Click on the link.

Old 01-29-06, 09:12 AM
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I hope you understand that the galv. is your prob., you have to get rid of it! Your rust is probably comming from the galv.

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