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Doug Miller

In article . com, wrote:
You guys are making this too hard. It's just pV=nRT (ideal gas
law).

So are you. :-)

1. Compressor takes in outside air, which typically has water vapor
in it, and packs it into the tank, thus raising the pressure.

And thus condensing the water vapor into liquid. End of story.

2. As you let air out of the tank, the pressure drops. This cools the
air (as p goes down, do does T).

3. Cold air holds less moisture so liquid water condenses from the
water vapor and collects in the tank.

Not correct. It was *already* condensed when under pressure. Water accumulates
in the tank during operation: air and water vapor, at ambient pressure, is
taken in by the compressor. As it is compressed, some of the water vapor
condenses into liquid and remains in the tank. Air withdrawn from the tank as
the tools are used contains less water vapor than the air that was taken in,
because some of the vapor remains behind in the tank as liquid. The longer the
compressor is operated, the more water will accumulate in the tank.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.