So what does it mean when you replace with new detector with new battery and it still chirps in the evening at random times? I went through and replaced the detectors only to have one chirp. Light will blink red every once in a while. Pulled battery and reset the unit. Still problems. Is it defective? My system links all of them with hardwire plugs with battery back up. Some suggestions have you install with power off then turn breakers back on.
Suggestions?