Archive for December 26th, 2015

Copper Pipe Corrosion Pinholes

When we moved into this house, I noticed a hose clamp around the half-inch copper pipe carrying hard water to the toilets and kitchen sink:

Hose clamp patch on copper pipe

Hose clamp patch on copper pipe

That’s obviously a whole bunch easier than removing and replacing a section of copper pipe, so I’d say it was entirely justified. The fact that it hasn’t leaked for at least the last quarter century counts for something.

However, Mary recently discovered a small wet spot on the basement floor. Looking directly upward, we saw:

Copper pipe corrosion pinhole - 1

Copper pipe corrosion pinhole – 1

That was in open air; I added the marks around the corrosion to highlight it.

I’d applied some foam insulation on the supply end of the pipe and, just to check, peeled it back:

Copper pipe corrosion pinhole - 2

Copper pipe corrosion pinhole – 2

Huh. Although that leak was slow enough to not leak out of the insulation (the slit was upward), disturbing the corrosion produced a regular drip. Again, those marks are new.

OK, two active pinhole leaks and a small dry green spot further downstream says it’s finally time to replace that pipe. The lengths of pipe with the pinholes add up to about eight feet, which suggests the plumber installed a bad piece of pipe back in 1955.

Yes, I applied two more hose clamps for the holiday season, but that can’t last.

Having a good stock of tees, elbows, and unions on hand, all I need is 21 feet (not 20, alas) of shiny new copper pipe to replace the entire run containing all the pinholes; I’m not going to fiddle around replacing just a few sections.