Carbon Monoxide alarm going off

[gitpicker2009]

I have two Carbon monoxide alarms. One just for CO and the other does CO and propane, and they're both going off.
The CO, made by Kidde, is reading over 350ppm.
What I don't understand is the TC camper is not being used, no generator, the propane tanks are closed and it's sitting under a carport as it always is.

I should add that they are both less than 2 years old!

I reset them both, and a couple of hours later, they're both going off.

Any ideas? Again, no gen running, no cars nearby, the TC is closed with a dehumidifier inside.

I'm stumped.

Thanks

[SAR_Tracker]

Any new fabrics onboard? I've heard CO detectors will alarm on the gas given off by cushions, etc....

[jimh406]

Different types of detectors can go off if dirty. Try some compressed air/canned air and see if that helps.

[gitpicker2009]

Yup, I checked and replaced the batteries, and it's plugged into shore power.
Plus when I opened up the coach and ran the fans, the levels dropped and the alarms stopped. ??

[cptqueeg]

If hard wired perhaps the back-up batteries are dead?

[gitpicker2009]

yes, thanks, I knew about the life span but these are both less than 2 years old. I've gone back and amended the original post. Thanks!

[naturist]

Carbon monoxide alarms have a limited service life of about 7 years from date of manufacture. If you allow for warehouse time, this means maybe as short as 5 years after you buy them. If yours are old, they will indeed alarm constantly to let you know it is time to replace the alarm. For obvious reasons, this is better than simply quietly ceasing to work at all.