In article ,
Mike Lalonde wrote:
Our Sears dehumidifier has been working for the last 7 years in our
business... running pretty much constantly in the basement. Must be
some extreme environment to corrode the tubing.

Dunno, as I indicated in my previous post.

There is a 3 year old water heater nearby (in the unfinished portion of
the basement) on which the new copper pipes are still bright and shiny.

The room where the dehumidifier operates has hundreds of CD's, CD-ROMs,
and DVD's - some over 20 years old - and none of the reflective layers
show even the slightest hint of corrosion or discoloration; yes, I've
checked.