Copper pipe is turning black

A. I would suspect exceptionally high sulfide levels. Is the strange smell anything like rotten eggs?

A. Could be Chinese drywall.

 > Hi David. Please flesh out your implication -- we have heard about this problem in general but we don't know any details. Thanks!

Regards,

A. I just moved into an 8 year old house and the copper pipes are black. Even the shower valve and pipe inside the wall. There was a rotten egg smell too. I don't know if this is the cause, inspection, I found that there was a small gas leak on the water tank heat control and another on a union. Repairing the leaks took care of the smell. Not sure if it was the cause of the black pipes. Also, the dryer vent was discharging into the basement, so that could also be a source of chemical to blacken the copper.

A. In 20 years of being in the Plumbing Service & Repair Industry I have ran across this blackened copper pipe problem before, Here is what I have found out ...
About 15 years ago in Stanton Ca I was called out to a small townhome community to repair a bunch of leaking pipes, copper water pipes, there were leaks on the main runs on some units, others were on branch lines feeding fixtures and Water Heaters, etc.

Well I attempted to repair on these lines, being careful to clean and prep each repair section ...
This pipe was almost impossible to solder.
After talking with others that had come across this problem before, I was told that Most of this pipe was imported from either China or Korea back in the 70's.
This pipe was very cheap and saved vendors and builders lots of money. The bad part about it is this pipe is so full of impurities that these impurities come to the surface as the pipe ages, so trying to solder it is like trying to solder galvanized pipe!
To this day there are still many tons of this pipe in warehouses throughout the U.S and it still makes it way to plumbing supply yards and home improvement stores.
One Job I was involved with the insurance company paid to have the building repiped in GOOD copper pipe. That copper pipe that turns black is substandard pipe with many impurities.

A. I bet my bottom dollar this is caused by counterfeit cheap Chinese copper pipes. This will turn the water blue and stain the bath/sinks, etc.
A brand new school in my town has had to provide bottled water for the last 5 years because of Blue Water.
DO NOT DRINK THE WATER.

A. Hi Dirk. At least two possible causes were cited -- namely sulfur ⇦this on eBay or Amazon [affil links] in the water and/or cheap Chinese pipe that looks like good copper pipe, but actually isn't (too much zinc and other tramp materials).

I don't think anyone can offer a definitive answer of which of several possible causes is THE cause from the single data point that the inside has turned black. But if you tell us whether you have city water or well water, what the water analysis says, whether other homes in your neighborhood were piped/re-piped at the same time, whether your neighbors report similar problems, whether your water is ever blue, if there are blue stains on the porcelain, etc., maybe someone can be at least a bit more definitive. Good luck!

Regards,

A. I wonder why should copper pipes be used for household plumbing- I thought it is too expensive. We normally use GI pipes and recently HDPE. Copper pipes are used in heat exchangers because of it good thermal conductivity. It is not difficult to analyse the contents of the pipes used and tally with what the manufacturer had promised. It is unfair to blame Chinese without doing proper homework!

A. Hi, H.R. -- Copper is surely the most widely used water piping material in the USA, although plastic pipe of various types is increasingly popular. Opinions about the safety of GI water piping vary here. As noted, we don't yet know whether Dirk's issue is due to excess sulfides in the water, low quality pipe, a little of both, or another cause.

opinion!  It is not improper for Keith and Alan to mention the fact that cheap, low quality, Chinese copper pipe and wallboard have been responsible for a lot of problems. It's not a matter of blaming another country ... but simply acknowledging the that there will always be scammers ... and if you build a distribution system which obfuscates the source behind layers of import/export complexity and multiple languages, and you make 'salad', you should expect scam products.
I recently bought a box of screws and -- instead of it saying "made in China" or "made in Indonesia" or "made in USA", it said: "made in one or more of the following countries (followed by a list of a dozen countries). It's not just the Chinese source to blame, but the distributors, warehouses, and builders who buy & install materials of dubious origin, and make things virtually untraceable while major damage is being done. And YES IT IS DIFFICULT for the average home owner to determine what specifications copper pipe should meet and to determine whether the pipes in their homes comply.

Regards,