Originally Posted by fritzeee
Thanks to all. There was a lot of good info. Some things I didn't know about, some I did. Turns out it is a bad battery with some bad cells. Put the other battery on line charged it up to full power per the trailer panel, pulled the plug on shore power and let her sit for a week. After one day power down to 3/4 and there it sat for the rest of the week. I need another bigger battery. That one is too small as one said. I'll try for the biggest one available.
when you do tests like this. Draining a battery too low, even a deep cycle battery, will definitely shorten it's life. Be aware there are a lot of parasitic power drains in a trailer, especially the LP gas alarm that eat up power like crazy just sitting. Your results of leaving it sit for a week and finding it drained down to 3/4 is not unusual at all considering the power drains.