I finally got around to dewinterizing the TT today. I was going to flush out the hot water heater and when I removed the drain plug, out came 1-2 gal of water. Apparently, it's been there all winter. I drain the water heater after every trip, so I'm a bit puzzled, but I apparently missed something somewhere last fall. I filled up the water heater and fired it up and fortunately no leaks. The only other problems found were a dead clearance light and the switch to the power tongue jack didn't want to work. I got those problems fixed in short order. Now all the TT needs is a top to bottom cleaning, and we'll be all set to go.
2008 Nissan Titan SE, Crew Cab, 4x4
Long Bed, Big Tow
I've seen folks who leave drain plugs out and then find critters nesting in the water tank next spring. I suspect you either didn't get it bypassed before someone turned on the pump or water or else you have a leaky or not completely closed by-pass valve or check valve allowing some back fill. Nothing too serious though since it wasn't full enough to cause a problem. I would also suggest that your water tank will probably last longer if you stop leaving it empty between uses. It's NEVER going to be completely dry and with a damp area like that it promotes oxidation. It would be better off left full during the summer months. Just my opinion / Skip