Smoke Alarm Won't Stop Chirping

Remove the battery from the smoke alarm. Put it in another battery-operated device to determine if it is working correctly. If the item doesn't work, the battery is bad. Replace the battery with a new one.

Push the reset button. Some smoke alarms have a reset button that when pressed tell the unit to check its battery supply and restart. If you do not push the reset button, the unit thinks it is still without power and continues to chirp. If this does not stop the chirping, you may need to replace the unit.

Check a hard-wired smoke alarm with a voltage meter. Turn off the power and disconnect the alarm from the wire that connects it to the power source. Place the wire on the voltage meter. Turn the power back on and see if the meter spikes. If it did, the wire is live. If it did not, the wire has a defect and is not receiving power. Consult a professional electrician for rewiring.

Check the side of the smoke detector for a sticker with a date. Sometimes, there is an installation date or replacement date noted. Smoke alarms should be replaced every 10 years.

Vacuum the vents on the smoke alarm or blow out the interior with canned air. Cobwebs, dust and even bugs can clog the unit and prevent it from working properly.

Check the manual for any further items to check. If you have done everything it recommends and the alarm still chirps, purchase a new unit.