Jack, you should have the house batteries turned on when using the coach and off when storing it. I know that you can get power to the coach via shore power connection and the converter is producing 12 vdc but you should not be operating the coach in this manner. You need to have the battery bank turned on for many reasons; one of which you have mentioned.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7