Yup, Doug and the previous few posts are the answer.
The "big appliances" such as A/C and water heater electric element are directly supplied from the main breaker box, not the inverter.
So, in order from breaker box, here are the potential issues:
1. 120 VAC from main breaker box not getting to inverter/charger. On edit: if this is the issue, the charger function of the inverter/charger would not be working either. If charger function working, move on to #2.
2. Transfer switch in the inverter/charger bad.
3. GFI tripped or bad-- again you have one or more GFI's that protect most of the outlets in the coach-- certainly those near any water (galley and bathroom).
