When we first got our rig in 2016 we replaced all the detectors.
But I didn’t notice the born on date for propane and C0 gas detector.
Last year it started going off when the camper was parked. I figured it was maybe from a build up of heat and it’s location right by the battery.
Finally during a pre-trip, pre-flight we tested the detector and it was bad. We tested both with the test button and released some gas next to it. It didn’t alarm so I pulled it off and replaced it. The build date only gave us a useful life of two years before the unit needed to be replaced. The new detector we made sure had not been sitting on the shelf for years like our first one. They only have a life span of 5 years or so it seems.
Which sort of sucks because it’s so expensive.
We lost a friend to a faulty furnace so we take it pretty seriously.