I have a Kidde i12060ACA smoke alarm that started chirping. I replaced the batteries and the chirping continued. I could press the 'hush' button and it would stop for 8 hours and would then start again. I finally called the Kidde Help line and they said to hold the 'Test' button down for 2 sets of three beeps, then release. This resets the alarm. Worked like a charm. Not sure why they don't put this reset in the manual....

Thanks Mary for posting your solution, no one should have to call Kiddie to find that solution, it should be easily available, thanks again Mary, !!

I recently replaced all 6 of my Kidde smoke detectors with the 10-yr lithium-type, (no replacement battery) because of this exact problem. They are all on one circuit. I thought that this would solve the "2 am" periodic chirping. Not so. However, I see that if the temperature drops overnight, this may be a factor. I find this frustrating, and frankly, ridiculous, as these units were significantly more spendy than their predecessors with replaceable batteries. I like to sleep with a cooler temperature at night. There HAS to be a better solution here.