when I came into shop this morning both carbon monoxide alarms were going off in camper. The camper is pluged in and gas is turned off. any ideas what could set off?
If stand alone unit, either the internal battery is dead/low or the unit itself has gone bad. They DO wear out.
If hard-wired, check the voltage of the big batteries, the output of the converter could be low or non-existent. Or, the unit itself has gone bad. They DO wear out.