Soldered pipe supports causing corrosion

The plumber decided it was a good idea to solder the pipes to the pipe supports. Each one had corrosion. I'm thinking that the solder increases the amount of galvanic corrosion between the dissimilar metals by providing a better electrical connection.

"Supply pipes in the main crawlspace had visible corrosion where they are soldered to supporting hardware. Corrosion appears to be the result of dissimilar metals electrically connected by solder resulting in galvanic corrosion. This condition may result in eventual leaking and these connections should be corrected or monitored for future leakage."

You are not supposed to Solder copper to steel.

The problem is the steel pipe "hangers". It looks like bent pieces of allthread to me Kenton.

Copper pipes need copper hangers or hangers that are coated with plastic/rubber.

Reccomend hiring a real plumber to repair.

They were actually the steel "U" hangers with the prongs you just hammer in. Very common here, but never soldered. Crazy plumbers!

That is the problem. Need to keep the steel away from the copper. Even tape or insulation would work.

They're probably manufactured for use with black steel gas pipe.

The other fastener they use here are the pound-in hooks with vinyl protection, but they lock the pipe against the joist and I think a fair amount of home noise comes from long uninsulated hot pipe runs throgh a poorly insulated crawlspace. Thermal expansion causes creaking.

It looks like the make Copper hangers like that also.

If dissimilar metals are used a barrier such as black tape should be used for the separation. It almost looks like a leak that repaired itself.

Mickey Mouse ears would be best for this installation.