I recently learned something interesting about CO detectors which has prompted me to post this.....
I didn't realize that newer CO detectors (made in the last decade) have a built in timer, powered by a small lithium battery
that counts down the service
life of the detector. This service
life was recently shortened to five years due to UL standards. This timer starts at the factory when the unit is assembled. A detector I purchased about 18 months ago, that I installed, began malfunctioning last month and I sent it to the manufacturer for testing. As it turns out it was manufactured over seven years ago and had reached its "timeout time". I wish I could recall
where I purchased it so I could avoid buying
from that place again since they are obviously selling units way past their shelf life with very little service life left. I didn't realize how pricey those things have become ....MSRP of $166 ....ouch...if you buy one be sure to check the circuit board for the manufacture date before you leave the store or install it. Fireboy/Xintex did offer me a unit for $120 but fortunately I can buy one at West Marine
for $119 minus the holiday discounts so that's not much of a deal. Hope this helps someone else avoid this issue....