I had my trailer in for inspection and explained the battery issues I was having. I asked them to test the battery and make sure the charging mechanism is working properly. They said both tested fine. I questioned the technician on why I had the issues I described. He told me that running the fridge on propane would drain the battery in 12 hours by itself because of the controller board. I find this hard to believe as the controller board (I assume) uses very minimal power. I just want to be able to make it 3 days with using the fridge on propane, minimal lights, and water. Am I crazy to think a single deep cycle marine battery will do this?