Properly maintained smoke alarms are one of the least expensive ways to provide an early warning for when a fire begins. Kidde make ionization sensor smoke alarms and combination ionization/photoelectric sensor smoke alarms for residential use. They can be battery operated or wired via the home's 120V power. Regular chirping of the device can indicate a potential failure. Here's how to troubleshoot your battery operated smoke detector if it starts chirping.
Remove the alarm from its mounting plate. Rotate the alarm in the direction of the "Off" arrow on the cover.
Insert a fresh battery in the battery slot. The Kidde P19000 and most smoke detectors are operated with a 9V alkaline battery.
If the chirping stops and the red LED lamp flashes every 30 to 40 seconds, this indicates the smoke detector is working normally again.
If the device continues to chirp, check to see if the chirp occurs between the red light flashes. If it does, this can indicate that components have failed. Return the unit for service. If it occurs at the same time as the chirp, your replacement battery is bad. Install another one.
Press the test button for 5 seconds to test the device. If everything is working correctly the alarm will sound. If the alarm does not sound, there is a failure and you should return the unit for service.