This is a timely thread for me. We brought our camper home from storage last night and I hooked up the battery (and shore power) when I was at home over lunch. I got back to the office and my wife called to let me know of the constant beeping. I thought she was talking about the smoke detector, but when I got home it was the carbon monoxide detector.
Our dealer doesn't have any service openings until June 19 (it's still under warranty) but we're going camping this weekend. YIKES!
So my general question is: Are carbon monoxide detectors user-replaceable?
(More specific question: ...replaceable on a Shadow Cruiser 282 BHS?)
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Update: Turns out it was a circuit breaker that had tripped. So even though it seemed like the trailer was hooked up to the shore power, the particular run that controlled the detector wasn't getting any electricity. Therefore, the beeping was a reflection of the low battery, just like so many others have pointed out already.