CO alarm going off--try cleaning!
Yup! While checking for real reasons is important; once you've done that, take your vacuum and clean the grill plate of your unit.
The CO monitors (had one on a TrailManor that did this occasionally) are sensitive to dust, dirt, animal hair; and a wiser man than me said, vacuum the thing--clean it--before you go buying a new one.
He was right.
Never happened again.
So give that a try; we try to keep ours clean on our rig now.
2014 8528 IKWS
Ford F-250 Diesel
Cassie the therapy dog and Cricket the Cairn