I recently sold my Rockwood 2270 tent trailer and upgraded to a Salem 26BH travel trailer. The new owners of tent trailer have contacted me to ask why the trailer will not run on the 12volt system if the have a site with no hydro. I never used the 12 volt system except for when i was towing the trailer I had the fridge running. Can someone help me out and refresh my memory what you have to do or check to get them up and running on 12 volts and what things run on it ( lights, fridge, furnace?)