LPG detectors have a service life of around 5 years. There "should be" a "replace before date" stamped on the back of the LPG detector and the owner's manual should address the service life. If this is the "OEM LPG detector" then chances are it's on its "second full service life". Time for a replacement. While you're at it, the CO (carbon monoxide) detector also has a 5 year service life as do most smoke detectors, so........ Yeah, more of your money spent by people you don't even know..... Trust me when I say that with an RV, it never ends....
Many say the two "happiest days" in any RV owners life are the day they buy it and the day they see it pull out of their driveway for the last time......