replying to jamesgangnc, Dan O wrote:
Actually I can tell you that deposits can and do build up in copper. Years
ago I replace a water heater with an indirect water heater. I was horrified
to see that after only a few years (3-5 or so) the hot water pipe output from
the heater had maybe half of its cross section left open. In general, folks
may be right that it isn't usually a problem with copper. However, in my case
I think my situation was worse due to the fact that I have a passive hot water
re-circulation loop. So the water lazily flows through the loop 24/7 - I
assume continually depositing calcium. Recently I added a softener for the
hot water feed. As a side note, we are on a township well with medium hard
water. I don't recall the number but remember looking it up an it wasn't
considered extremely hard.

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