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What Do Smoke, Fire, CO Alarm Beeps, Chirps Mean?

Here are what the chirping / beeping codes from First Alert mean, for the smoke / fire / CO detectors:

  • 4 Beeps, Pause, 4 Beeps: EMERGENCY. This means that carbon monoxide is detected in the area, you should move to fresh air and call 911.
  • 3 Beeps, Pause, 3 Beeps: EMERGENCY. This means either smoke or heat is detected, you should leave and call 911.
  • 3 Beeps Every Minute:, this could mean the alarm is in a malfunction mode.
  • 1 Beep Every Minute: Low Battery. It is time to replace the batteries in your carbon monoxide alarm.
  • 5 Beeps Every Minute: End of Life. It is time to replace your carbon monoxide alarm.

These are pretty common across most devices, but you can always Google your particular brand / manufacturer to get the exact codes.

When it is time to replace your alarm / detector, which was about 5 to 7 years for older models, and up to 10 for the new ones, you should consider the combination smoke / CO. These don’t cost much more than the standard smoke detectors, but can save your life.

The First Alert Smoke Detector and Carbon Monoxide Detector Alarm, (uses 2 AA batteries) is under $30. This is one the of the highest rated, and most reliable devices on the market.


Newer models also come with built-in 10-year batteries, so you don’t have to worry about replacing batteries twice annually (recommended to do when you change the clocks to/from daylight savings).

For more advanced units with additional features, check out our review of  Best WiFi Smart Alert Smoke and Carbon Monoxide Detectors for 2018 .

Be sure to check out why your alarm / detector is beeping, and stay safe!

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