Originally Posted by D Lindy
I know that the general train of thought is to run the genny while driving with the furnace on.
Where did you get that idea?
If everything is working correctly
it's not necessary to to run the genny while driving with the furnace on.
The generator only needs to be run when driving if you want to run the rooftop A/C or heat pumps or electric heaters.
All other electrical requirements, (both 12V and 120V), will be satisfied by the output of the alternator and/or the inverter.... (including the 120V power for your residential fridge).