Originally Posted by Adagio
Can you use it when the van is driving? Yes, just turn on the inverter.
Can you use it when the motor is no longer running but with generator? Yes, but inverter still needs to be on.
Can you only use it when hooked up to electricity? Yes, but inverter charger needs to be on.
If your battery bank is large enough, you can also run the A/C while parked. Time you can run dependent on bank size.
Without know what brand and how big the inverter is, some of this may or may not be true.
If the inverter is big enough and the alternator or second alternator and wiring are big enough you could run the coach AC without running a standalone generator. If not you need to run the generator.
If the van is not running and inverter and batteries are big enough they will run the AC for a while. If not big enough you need to run the generator. Most inverters would not need to be on as it is the same as shore power auto switching.
When on shore power it should autoswitch to it to run the AC and the inverter would not need to be on, but the charger would, as they are normally controlled separately on most inverter chargers.