Well I finally tested the water system since I dry camp a lot to prove or disprove whether the water system works as advertised ? I followed the directions on the door that explains bringing water through gravity/ pump system ( dry camping). First you switch the water valve to sanitize/ winterize then you turn the valve next to main valve to bypass. There is a little knob / switch below them that is not labeled. You turn that to open. Just follow the picture directions on the door. I filled my 45 gal portable water bladder on my tailgate. Then I hooked a regular white potable water ( standard) 15-20 ft I believe to my bladder and the other end to the kantleak valve. I then opened my bladder which was actually below my kantleak valve. I then went inside turned on the pump. It took a little while but it pulled all 45 gal in my tank. Worked as advertised. Great system! Makes my life easier!