I'm getting ready to leave on a trip tomorrow, so I wanted to test the gas mode of the fridge to make sure it works. AC had worked fine. I switched to gas and left it for a bit, maybe 20 minutes. When I came back the trailer smelled funny - not like propane, more like just "hot". I don't really know how to explain it. The cabinet on top of the fridge was warm, and the outside hatch was pretty hot as well. Is this normal? I turned it off because I got nervous.