Some of the Class Cs do not charge house batteries off the alternator. The coach has to be plugged into shore power or have the generator supplying power to the coach for battery charging to be in effect. Do you have and know how to use a volt meter? IF so you can check voltage of battery before and again after starting the engine and verify if the voltage increases or not on the battery bank for the house. Good luck, stay safe and keep us posted.
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