We have the 2017 Chateau 24F. No lights in the right side storage cabs. Our dinette has cabinets in the slide and lights with a switch below them. Main coach is filled with lights and bedroom curtain contains all the bedroom lights. We have a standard 1.5x3 gray & black waste connection that is very low, much to my dismay. Your pic is difficult to see where your gray water dumps. Yes the dual black water valves keep the solids from dropping down into the drain line and causing a blockage.
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