I have read that pinhole leaks are generally caused by corrosive water. Remember, not just
anybody can test water for corrosivity. It can be a rather complicated process. For example,
if the water is relatively soft, AND the PH is a bit low, then you can bet they'll probably
be problems. These problems individually don't seem that bad. Also, the presence of sulfates,
oxygen, and carbon dioxide can inhibit the formation calcium deposits on the inside of the
pipe, which protect it. Again, only an expert can put together all the pieces of the puzzle to
get the real story of what's going on. The flux company said that it can't be the flux.
But is he an expert in water chemistry and corrosion? Probably not.

In Florida, there is an epidemic of copper pinhole corrosion problems due to drawing water from
deep wells where carbon dioxide, sulfates, and oxygen dissolved in the water has cause major
copper pitting problems. In these areas, many codes officials require the use of CPVC piping now.

I would recommend taking a water sample and sending off to an expert on pipe corrosion problems.
A water treatment company (Culligan, Rainsoft, etc.) may be able to pinpoint the problem and
recommend a treatment. If not, you may want to consider replacing the copper piping with CPVC
or something otherwise effective in handling corrosive water.

Also, make sure that there's no galvanic corrision going on with disimilar materials in direct
contact. If the corrosion problem is primarily around fixtures, then it may be something going
on at these locations. Make sure the plumbing hasn't installed, for example, a galvanized steel
nipple or something like that in direct contact with the copper tubing at the stop valves, etc.
With certain water chemisties, this could cause major corrosion problems.

Hope this helps.
Ed Hale, BSME, CIPE/CPD
Smith Seckman Reid, Inc.
Consulting Engineers

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