2001 H345 Vantare. Connected water supply & turned on, fresh water fill switch not operating, about 5mins later water overflowing from fresh water tank. Went to connect sewer hose & found fresh water (I assume) draining thru discharge line with black & grey water tank valves closed. Anyone got a direction for me to take for troubleshooting ?
Got water at faucets & toilet flushes also.