Doug Miller wrote:
In article , "Leon" wrote:


You are on the right track.
Actually the compressed air does not create the condensation. It is the
heat generated from compressing the humid air that causes the condensation.


Incorrect. It is *exactly* the compression that causes the condensation: water
that is vapor at ambient pressure can be condensed into liquid by increasing
the pressure.
After reading your post, it reminded me of the fact that in order to
bottle liquid oxygen, they have to cool *and* put it under high pressure
to get it to condense to a liquid, but I never would have thought to
apply this principle to an everyday compressor. Good info.