Kidde C3010D Carbon Monoxide Detector, 10-Year Worry-Free DC Sealed Lithium Battery Powered w/Digital Display (21010075)

This unit was manufactured on 10/26/2020, bought and installed in June 20214 years into service. No chirping but display shows a yellow fault upon testing. Or, is this just to ensure that the display light is working? Important to know.

Unit started beeping and displaying Lb after 4-5 years.

Life saving indeed. I recently bought a used 1990 class B Campervan with dual electric/propane appliances. (Fridge/stove/Furnace). In the road with it this past week, I've heard the furnace come in due to the cooler nights. Its not cold enough to depend on it and so I decided to disable its operation.Two days and nights pass with no issue. This morning though at 5:am I am awoken by a persistent hi pitched pulse alarm. I'm confused and foggy and begin flipping switches for pumps that may have been bumped on. The alarm continues and I've now noticed the furnace is running. Not throwing heat but running.I open the side and back push out windows and then proceed to find the source of the alarm. This was made decidedly harder as a change in pitch deceptively hid the location. Eventually pinpointed and found at the back of a drawer. The previous owner had left behind a KIDDE carbon monoxide alarm which was registering 40ppm. I'm assuming the levels were rising and with me normally rising after 9am, it's quite possible that I may not have risen at all. I am grateful the previous owner left the unit and doubly grateful for the quality and effectiveness of the monitor. The previous owner had the vehicle for 4 years. The vehicle sat idle for the year prior to my purchase. I'm guessing it was bought and unstalled 4yrs ago. The lithium battery is rated for 10 yrs and confirm it is working in year 5. Thank you for your attention to quality. Without it, i wouldn't be able to provide this review

Bought in the winter, it's now beeping at me at 3am screaming it's low battery, but you can't change the battery in this model. Don't know if I can disable it or not to get the warranty done as website doesn't say.

Had this up for YEARS and nothing ever from it. Woke in the middle of the night with over 150 ppm. Pulled all the kids out of the house and called emergency to come out and check. Readings were up to 300 ppm and no one could enter the house. Furnace failure to vent properly could have kill us and our kids if not for the alarm. It's a lifesaver. Literally came to post this review saying this for others to see.