First time using the Carado Axion van. Last night I hooked shore power up to house receptacle 110 (had 15amp adapter) in order for fridge to cool, but got nothing. Batteries had depleted to 7.65, so lights were very dim. Do I have to hook shore power up to 30 amp receptacle for van to get shore power? All breakers are still on, but I'm not getting power from the house. Please advise. First time using a camper van.