I'm having a problem with a fairly new (2+ years old) GE reverse osmosis unit. The unit will not refill after emptying. I have changed out the filters. One of my children was playing around and let some air out of the pressurized storage tank. Some one told me that it takes 7-9 psi and I've filled it with approx that amount, but no go. If I take apart the filters and unscrew the shut-off cover and take out and put back the check-ball assembly, put it all back together, it will refill!!! But once it's full it won't recharge unless I do it all over again. Does anyone have any ideas??? It seems like it would be a simple fix, but I can't wrap my head around it.