The designer of my compressor unfortunately didn't put a whole lot of thought into where to put the drain valve on it. It's on the back, and the compressor is against the wall, in a corner, usually with a mower or something backed up to it. Draining my compressor is a pain in the butt.
So I did something about it! I went out and get the appropriate adapters to have a hose coming out the bottom of the compressor and just loops around the top. Something like this.
________
| |
/ \
/ Motor \ | |
|__________| | |
/ \ ( x ) Drain valve
/ \ | |
| | | |A
| | | |I
| Tank | | |R
| | | |
| | | |H
| | | |O
| | | |S
| | | |e
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
\____________/\_//Connection to old
[] [] \_/ drain valve location
As you can see the water travels "up-hill". At first this doesn't sound right until you realize that the water travels "up-hill with 40-120 psi of pressure pushing it". I can't see a problem with this, but would love to know if there is some evidence that this is acceptable, or if this is a bad practice, given the cost of a new compressor.
Best Answer
As long as you purge the tank until the moisture out you should be fine. I maintain some big compressors 150-200 hp that all push up into a separator tank to make sure any oil is removed from the water then the oil drains back to the compressor and this is a commercial setup. I am guessing you have a manual valve, when there is very little water vapor coming out you should be good.