Fridge should be on 110; no impact on the converter.
The radio, the heater's fan, the water pump, all lighting (inside and out), the awning and the battery charger should be all that are on the converter.
Must include the igniters for the heater and water heater. And the CO/Propane detector.
Did you check the bathroom fan?
TT 2015 19RD "TheJayco"
TV 2003 F-350 "Montblanc" - Housebroken chore truck
Sitting in The Cheap Seats.
And proud of it!