tankless water heater question

[Brett Hartwig]

I have a tankless water heater, been working fine now for 4 years. Over the last couple months I have noticed a lot of bluish/turquoise deposits on the copper pipes, mostly the cold pipe. No wetness so far. What would be causing this? If it's just discoloration because of the copper, I don't really care. But is it slowly eating away at it until a leak springs when I am at work someday? I will include a picture

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[Ed Fenwick]

Aloha freeport, thst is how copper rusts. It will eventually go through but take a long time. Youi could clean it off and put some grease on it just as you do the battery posts.

 

[Brett Hartwig]

ok, thanks

 

[Gavin Allan]

What's the pH of your water? Sounds like you have slightly acidic water?

Around here, copper pipes will last 100 years or more. In areas that have slightly acidic water like central Florida, they are lucky to get 20 years out of copper pipes.

 

[Richard L]

Freeport,

It appears that the Tank-less hot water heater is installed outside (very typical). That means your copper pipes are exposed to all the elements which causes more corrosion of the pipes.



Also, if a lot of flux was used in soldering the joints and not cleaned off, that is an acid that can cause rapid corrosion.



Sometimes you can get an electrolysis action when dissimilar metals are connected together. In your case, the coper is joined to brass, whis should not cause any electrolysis problems, and it appears that you have Teflon tape on the threads where the shut-off valves connects to the water hearer inlet/outlet, which should help reduce that problem.



I don't think you have a major problem, but just keep your eye on it for leaks. If it should start to leak, at least it's outside and not likely to cause any damage, and there is plenty of good pipe left to simply replace the bad section of pipe....and it would not be too expensive, even at plumbers pay scale.



...Rich



...Rich

 

[swshawaii]

Have the same issue and thought about covering them with foam pipe insulation. My concern was the foam trapping

the condensation from the cold water. Left them bare, and 20 years later they are still blue/green and doing fine.

BTW, DO use foam insulation on the HOT water pipes. It works and is very cheap. :banana:

 

[Jackson Ellis]

Another example of untreated copper...

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[Brett Hartwig]

Thanks for the replies. BTW rich...the water heater is mounted inside, on the basement wall and vented outside

 

[Gavin Allan]

Got any strong or corrosive chemicals like fertilizer or water softner salt stored nearby?



Natural Gas heated? Exhaust gas from natural gas is very corrosive.



Does not lool normal to me, especially on one side but not the other. The top pipe may have a small leak?



I would not be so fast to dismiss it. I would want to know what is going on and to try to prevent it.

 

[Richard L]

Freeport,

You have a basement in Florida?? You must be one of only a few basements that exist there.



Is this a true basement or is your main house elevated and what you are calling the basement is actually at ground level, and not really below ground?



You could take a wire brush and scrape off the corrosion on the pipes and check for leaks, but you said their is not leaks, and I would think that any leaks would show on basement floor??



Again, I don't think you have any serious problem, just check it out every month or two to be sure a leak is not developing...That would be a sign that you need to replace the pipe/s



...Rich

 

[Brett Hartwig]

Not florida...i am in wisconsin. full basement with 9'walls

 

[Richard L]

Freeport,



Sorry. For some reason I though you lived in Florida...I thought I clicked on your profile and it said you lived in Florida???? Now your profile says you live in Illinois, but you say you live in Wisconsin? Do you move a lot??...:grin:



...Rich

 

[Brett Hartwig]

lol...nope never lived in florida. I moved to Freeport IL when I got hired by their fire dept, then moved back to my hometown in Monroe, wi but still work for Freeport Fire Dept, about 20 miles away

 

[EddieS'04]

The chem plant I worked in. We would coat, those type of copper instalations. With dow-#5 silicone grease, on new installations. Worked good.

 

[swshawaii]

Copper oxidation almost buried the Monster Cable company in the early eighties. Got their start making affordable 12 gauge speaker wire with heavy clear sheathing.



Problem was it wasn't "oxygen free", and it all turned green or black inside. Didn't affect audio quality or performance the least, just looked awful and wasn't saleable.