CO2
If it is a Co2 alarm, do not assume it is malfunctioning. Get fresh air and call 911.
BATTERY
If it’s a battery powered alarm, chirping might indicate that it needs the battery replaced.
When our neighbor’s hard wired smoke alarms were going off and it was difficult to figure out why. After changing the batteries in all of them, the alarm went off again.
Changing the batteries did nothing, because they are there as backup if the power goes out.
I just happened to disconnect the smoke alarm that was the faulty one.
Here are some tips I wish I had known earlier.
WHICH ALARM WENT OFF?
Here’s info from Kidde to help determine which alarm is the one that triggered them all to go off:
“If you have interconnected alarms, the first step is finding the initiating unit, as that is the key to stopping all of the interconnected units from sounding: To find the initiating unit, look for one that is flashing RED or GREEN at least once every second while in alarm mode, then follow the reset procedure on that unit. If the alarm stopped on its own before you could find that flashing light, the initiating unit will flash for 1.5 seconds every 10 seconds. If there are no obvious signs of a fire, the alarm should be cleaned before being reinstalled.
False alarms are most commonly caused by something interfering with the sensor. To clean, after disconnecting the alarm and removing any removable battery: hold the unit by its edge and thoroughly blow through the gap on the side of the unit with compressed air (like keyboard cleaner). We recommend cleaning out all of your smoke alarms at least every 6 months to a year and at this point we would recommend cleaning out all of your other alarms as well as a preventative.”
Found this a number of places on their website, https://www.kidde.com/home-safety/en/us/products/fire-safety/smoke-alarms/
DRAIN THE ALARM
“You can take them down and take the battery out. After you pull the battery out you can hit the test button to drain the remaining energy out of the alarm. Or you can push the test button if it is going off and it will reset if it doesn't detect smoke.”
TAMPER RESISTANT PIN
Also, one one of the smoke alarms I could not twist of off. This is because it had a ‘tamper resistant locking pin’. You can remove that with needle nose pliers.
