Originally Posted by 08flagvlite
One question. Do you have a pressure regulator on your city water inlet connection? If not, then you never really know what the water pressure is at different campgrounds, so the pump's check valve gets more pressure than it was designed to stop, and thereby leaks backwards slowly into your fresh water tank. I was baffled by that same discovery on mine, and corrected the problem with a pressure regulator (about 10.00).
Hope this helps, Randy
Excellent idea. All of you guys. Really like this forum. I will try the pressure regulator first. Then I will begin taking things apart from there.