Originally Posted by weed wacker 2
Look fellas.. The bottom head drained for a little over 5 minutes after the system was off. This is with the bottom end head off. If it were a valve stuck there would be a constant trickle of some sort. The problem is solved. No need for all the smart ass comments because I'm sure all of you were geniuses at birth.
OP states problem is solved. Time to move on from this one