Used RVs and old sensors, safety first
Last year I bought an older RV, 2005, from a private party and I didn't really know anything about them. It just sounded fun (which it is) and I was more concerned filling it with things I would need that I overlooked something very important.
The sensors, it wasn't until one of them went off repeatedly on my last trip that I gave any thought to them. Prior to this I did put the battery in the smoke detector and put it up while on a trip but I never looked at any of them. It was the propane sensor going off, we didn't have the propane on and I couldn't smell it and I'd had the propane system inspected recently. Fortunately I have all the paperwork for everything from the original owner. I discovered this sensor should have been replaced years ago, the CO sensor actually says on it to replace it in 2007. I'm sure this went off due to it's age but we were careful and kept the propane off most of the time, it was a pain. That's when I decided it would be best to replace all the sensors including the fire extinguisher when I got home. In my research I discovered everything should have been replaced a couple of times by now.
I'm waiting on one sensor but I've replaced the other sensors/fire extinguisher and put dates on them. I should have been thinking of those first not last. I suggest if you're looking for a used RV, look at replacing the sensors and fire extinguisher when you buy it or at least research when they need to be replaced, it's inexpensive and easy to do.
Due to my RVs age I plan to get the propane system inspected annually, it was the one thing I felt I did right.