Corroded copper ever reseal itself?

[Richard Moore]

This is kind of an odd question, but...

I had a very basic 1989, 2 story with crawl, home today. Most of the copper piping in the crawl was hung using steel hangers and many areas looked like the photo. I'm calling for a plumber to go through the whole crawl to replace the hangers and piping as needed (insulation also needed).

I had two small pools of standing water on top of the moisture barrier, both directly beneath badly corroded areas (the photo was one of them). One had only a cup or two of water and the other, maybe a gallon. It may just be coincidence that the pools were directly beneath corosion, but both were otherwise located so that I couldn't envision the water coming from anywhere else but the water pipes above.

My "problem" is that neither area was actually showing any signs of active leaks. The house had 120-psi static pressure (another issue). So...while I strongly suspect the water is coming from the corroded piping, it just doesn't seem likely unless such corrosion could intermittently reseal itself. Can that happen?

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[Jim Katen]

Originally posted by Richard Moore

So...while I strongly suspect the water is coming from the corroded piping, it just doesn't seem likely unless such corrosion could intermittently reseal itself. Can that happen?

I've never heard of that happening with copper tubing. Once it starts to leak, it keeps leaking. It's not like steel pipe, where pinhole leaks routinely seal themselves with rust.

- Jim Katen, Oregon

[gtblum]

Had it happen in my own house Richard.

I opened the leak while i was checking it out OOPS!

Mine was galvanized.

[Richard Moore]

Originally posted by Jim Katen

Originally posted by Richard Moore

So...while I strongly suspect the water is coming from the corroded piping, it just doesn't seem likely unless such corrosion could intermittently reseal itself. Can that happen?

I've never heard of that happening with copper tubing. Once it starts to leak, it keeps leaking. It's not like steel pipe, where pinhole leaks routinely seal themselves with rust.

- Jim Katen, Oregon

Yeah, doesn't seem too likely does it, especially with water pressure that high. One other option is rat piss (lots of nests in the insulation) but it tasted like fresh water. [:-chef]

Jim...assuming it's not the pipes actually leaking, and with the proviso that I'm going to leave it up to the plumber, do you think that some will still need to be replaced based on the corrosion in that photo? There were a LOT of similar areas.

BTW...good to see you back posting on a regular basis. Are you also back at work yet?

[Rob Amaral]

I've seen it a lot. These leaks start out microscopic, slowly advance. Minerals in the water and the corrosion can work together to seal them. I saw some 1980's water pipes (copper) with huge crusty blooms of mineral flowering just a couple of weeks ago. Moral of this story is 'don't scrape the scab'..

[Chad Fabry]

The less noble metal is corroded preferentially over the more noble metal; it becomes anodic. The deposits are likely the result of salts in the condensate being shaken out over the electrically active area. It's quite possible that there is little or no damage to the copper.

[msteger]

I would have guessed that minerals in the water would have sealed the leak(s) over time.

[J Howland]

It look like the bracket was solder to the pipe. The bracket is steel with a copper or brass coating. After bending the wire around pipe and heating it up could have damaged the copper of brass coating on wire bracket, allow a reaction between the two metals. The pipe must have condensation collecting on it for years, you can see the rust on wire bracket.

[J Howland]

I am new to Forums and posting on them. I will edit my post a little closer in the further and read the whole string before posting.

I think Chad Fabry is right about the noble metals. I have also seen solider flux that was not whipped off, do something similar in unconditioned spaces.

[randynavarro]

Welcome John.

I don't think you committed any errors. As a gifted writer and home inspector, Walter J (SonOfSwamp) is one of the best at helping us think more concisely and logically about what we write and ultimately communicate. At least that's how I read his previous comment.

It'd also be helpful if you filled out your bio. Are you an inspector, plumber, fireman?

[Erby]

C'mon WJ, it's easy.

The dominatrix missed whipping off the solider flux but whipped the heck out of the softer flux! That's why only the solider flux is still there!

Another light moment brought to you by John Howland. Thanks, John. I needed that. [8][8][8]

Don't sweat it, John. WJ gets all of us every now and then.

[Erby]

Rawhide, Hyah!

[utube]http://www.youtube.com/watch?v=GP2mcVwQ2as[/utube]

Though flux isn't the usual target.

Kentucky ranks 8th in the nation for the number of beef cows.