What is needed is a dual chamber detector that will detect CO and smoke from a slow smoldering fire such as may start in a R/V because of electrical fires and fast burning smokeless fires.
After a lot of research and talking to Kidde, they assured me that this one would work in a home and also A RV,there is no difference.
This is what I found.
A Kidde KN-COSM-XTR-BA Nighthawk
That seemed to be best suited for this kind of application.
Like This They now can be bought at Home Depot, also At Amazon.
Home DepotAmazon I suggest you read all the info and make your decision on this but I replaced the ones in my Class C with this one.They are rated for 10 years
and most are only rated for 5,If your RV is older than 5 years old and they haven't been changed they are most likely no good. Mine needed to be replaced so this was a good deal for me, I had a hard wired one and I chucked it for the battery powered ones, they can be checked before each trip by pushing the test button in the center of the unit.