"Leon" wrote in message
t...

"Mike Marlow" wrote in message
...



Close but not quite. It's the act of compressing the air that causes the
water build up in the tank.

It's the heat generated during compression that causes condensation to
build up in the tank. Compress air with out changing the temperature and
you have no condensation during that process.

It is actually the cooler tank and air lines that causes the vapor in the
heated air to condense. That is why large systems use refrigerated dryers.
The moisture is already in the air, compressing it concentrates it into a
smaller area.