I've got the same problem. (And yes, gamachinist, I drain the tank frequently!) Your idea sounds plausible to me, but I know very little about air dryers. I assume you know that the water separator ought to be put at the point of use, not at the tank.
Try to make a living, not a killing. -- Utah Phillips
Don't believe everything you know. -- Bumper sticker
Everybody is ignorant, only on different subjects. -- Will Rogers
Law of Logical Argument - Anything is possible if you don't know what you are talking about.