Mine is simple switch panel larger AH power switch and smaller elect. element switch to left under sink.
The AH is diesel right?
The LP smell is probably second issue. Gas valve should be full open or closed there seat for both but stem packing may be leaking and can be tightened. Most tanks have a hose right after tank prone to degrade after many years. Spray bottle with dish soap and water or kids bubbles and start spraying all LP connections, regulator diaphragm , hoses, valves.
EDIT. I reread title and post.....it will no turn off... There should be a main 12v fuse if anything . I would imagine there is a smell if AH is running they burn clean but still have a smell.
95 Monaco Crown Royale
M11 400hp, 4060 trans.
Aquahot, Generac Guardian7.5k