"AJScott" wrote.
(HA HA Budys Here) wrote:

I've seen some copper joints with a greenish ick around them, sometimes
culiminating in a 3-dimensional chunk of chalky ick. What is that?


That ick comes from electroylisis, which in the plumbing world, happens
when two different types of pipes come into contact with each other, and
the results tend to show up at the joints, as you noticed. Most often
happens when someone uses tin/galvanized hangers to tie the pipes to
wood structure, or lays conduit right over the copper pipe without
sticking a piece of wood shim or cardboard or hunk of foam or whatever
to prevent direct contact between the two un-like pipes, or when someone
replaces a section of copper pipe with galvanized without using a
dilectric union, which is made of plastic, rubber and brass (brass
doesn't react with other metals, which is why brass is used for pipe
fittings).

AJS

It can be caused by soldering flux too, which if it is happening at a
fitting, it's much more likely it's flux. Brass does too corrode, just more
slowly.

Gary
Quality Water Associates
www.qualitywaterassociates.com
Gary Slusser's Bulletin Board www.qualitywaterassociates.com/phpBB2/