Hi all, I have a new Fuzion Toy Hauler that has the side door for all the water hook-ups. One for city water/winterizing, one for the fresh tank fill, and one for the black tank flush. I'm trying to flush the lines clean from the anti-freeze and the only way it will take water is when I turn the little valve to winterize. When I turn the winterize valve off, all the faucets shut off. I thought when you were hooking up for water, the winterize valve should be off. Is that not right or is something wrong? Please clear my thinking on how all these valves and water hook-ups work.