[Carl n Susan]

Even if you used the battery disconnect switch in the convenience center (which doesn't cut off all the 12V load), the battery will go dead is a short time. Either install a battery disconnect switch at the negative side of the battery or remove the battery when you store the RV. A fully charged battery will last for a long itne *IF* it is totally disconnected from the 12V system.

Your existing battery is probably toast as they do not respond well to being fully discharged.