All the lights, water pump, fridge while on gas, furnace, water heater if you have electronic ignition, and radio. TV and Micro are the only two things that "need" 110. When you are plugged into 110 the converter supplies the 12 volt for all the above and also recharges your battery. The fridge can be set to run on 110 as well to save propane, but it still needs 12 volt to operater the control circuits.
PINNACLE 2015 38FLSA. aka: "Roam Sweet Home"