Having just picked up a 2007 Fleetwood E-3, I have a few repairs to make. Is that a carbon monoxide detector or a smoke detector that is supposed to be hardwired in the ceiling? The first owner removed the original equipment for some reason (presumably, because it was defective or broken) and replaced it with a battery powered carbon monoxide detector. It does not want to stay in place since the replacement unit is designed for a wall application rather than a ceiling application. Should that be a hard wired carbon monoxide detector or a hard wired smoke detector? (Shouldn't a carbon monoxide detector be mounted low on a wall, since the gas if heavier than air?) Any ideas where I can get a replacement? Would it be the same as the units people put in their houses? Thanks for your thoughts and suggestions.