We have exactly the same problem in that we cannot leave the trailer disconnected from AC for more than about 24 hours without falling flat. I've had this unit back to ExploreUSA, this will be the third time. Has anyone gotten Redwood's manufacturer involved? I actually had the guy at ExploreUSA put a 50 amp fuse in place of the blown 25 amp fuse in my truck, said 25 amps not enough for battery charging. I suppose he doesn't care if he melts the system in my truck, so I changed it back to 25 amp immediately.