You have a choice of 'auto' or 'gas', if you run on auto and you are plugged into shore power or if feeding 110 volt from a generator the fridge will run on 110 volt. If you are not using 110 volt while in auto mode it will check for the presence of propane and automatically switch to gas if present. In either case (gas or 110 volt) the fridges controls are ran by 12 volt battery power so yes you must have 12 volts available even when on propane or it won't run. If 110 volt is available your TT your TT converter will provide the 12 volts to charge the battery thus supplying the fridge as well. The TT heater uses propane for the flame but uses 12 volts for the control circuit and the fan motor. Your battery disconnect switch needs to be on at all times when camping or stuf won't work, this switch is more for when the TT is stored or not in service. You need a way to keep your house batteries charged the options are: Shore power, generator, solar. Do not rely on you TV to charge the house batteries. The same things apply to a MH except the chassis battery/alternator does a better job of charging the coach batteries than the TT setup.
Dale & Terri, Lulu & Tiki (our Chihuahua's), New rescue puppy Prince - Pom/Pug mix.
2013 Tundra, Double Cab, 5.7, TRD Off-Road, 4X4, Full Tow Package
2013 Wildwood T26TBSS - Sold
2000 Gulf Stream Sun Voyager M-8357 MH, Ford Trident V10 Gasser, 35 foot.