First alert carbon monoxide alarm end of life sound

Carbon Monoxide Detector Replacement FAQs

Carbon monoxide detectors, commonly shortened to CO alarms, need to be replaced regularly in order for them to continue operating correctly. Whether you have a non-digital, digital, or combo alarm, there are signs to watch out for in order to keep yourself protected.

Learn How Often to Replace CO Detectors

Carbon monoxide detector replacement is crucial to keeping you and your loved ones safe, especially if your CO alarm is starting to near the end of its life span.

Is your carbon monoxide alarm beeping? To determine if your alarm is at the end of its life, refer to the following:

  • End-of-Life warning will sound every 30 seconds

  • If the alarm has a digital display, it displays the ERR or END error code

  • The beep will ONLY STOP when the alarm is out of power

  • Replacing the battery WON'T STOP the beep

Carbon monoxide alarms do not detect the presence of carbon monoxide when in end-of-life mode, which is why it's important to take precautionary steps when you realize your CO detector is nearing time to be replaced.

Do you have a non-digital carbon monoxide alarm? To determine if your carbon monoxide non-digital alarm has reached its end of life, refer to the following:

  • When the CO alarm emits a quick beep every 30 seconds and the red LED flashes, you may need to change the batteries.

  • Replace the batteries in the alarm

  • If the alarm continues to emit a quick beep every 30 seconds and the red LED flashes, the alarm has reached the end-of-life.

To determine if your combo alarm has reached its end-of-life, look for these signs:

  • If the alarm emits a chirp every 30 seconds, it is either an end-of-life alert or a sensor error

  • If the alarm emits a chirp every 60 seconds, it indicates the battery power is not sufficient to power the unit in full alarm

  • An end-of-life or sensor error will not respond to a battery change

How Long is a Kidde Carbon Monoxide Detector Good For?

In 2009, Underwriters Laboratories (UL), began requiring an end-of-life warning to alert homeowners when their carbon monoxide alarm has reached the end of its useful life. As an industry leader committed to safety, Kidde has included this feature in all its carbon monoxide alarms since 2001. Kidde carbon monoxide alarms have a proven life of seven to ten years, depending on the model type.

As of 2013, ALL Kidde carbon monoxide alarms have a 10-year life, with the following exceptions: Model KN-COEG-3, KN-COPE-I and KN-COPP-3. If your CO alarm was manufactured before 2013, it has a seven-year life.

If you're unsure of your alarm's age, look for the manufactured date on the back of the alarm.

In accordance with the National Fire Protection Association (NFPA), Kidde recommends replacing smoke and heat alarms every ten years and replacing carbon monoxide and combination alarms every seven to ten years (depending on your model) to benefit from the latest technology upgrades. Carbon monoxide detector replacement is a quick way to ensure that the presence of CO is detected accurately.

For more assistance, please email or call Kidde Consumer Product Support at 1-800-880-6788 Monday through Friday from 8:00 AM – 5:00 PM EST Saturday 9:00 AM – 3:00 PM EST.

Back to Support Center

First alert carbon monoxide alarm end of life sound
CO alarms need to be replaced every 7 years

The Seattle Fire Department has received multiple 9-1-1 calls this year from concerned residents because of chirping carbon monoxide (CO) alarms. While it’s important to call 9-1-1 if your CO alarm is sounding continuously without stopping, a CO alarm that chirps every 30 seconds is not an emergency. It probably means your CO alarm has reached its end of life and should be replaced.

CO alarm life span

CO alarms have a life expectancy of around seven years. All CO alarms produced after August 1, 2009, have an end-of-life warning notification that alerts the resident that the alarm should be replaced. The CO alarm will beep every 30 seconds or display ERR or END.

If a CO alarm is at its end-of-life, replacing the battery will not stop the beep. Some CO alarms have a feature that will silence the signal for 30 days, but this will not solve the issue as the CO alarm will continue to beep after the 30 day period ends.

First alert carbon monoxide alarm end of life sound

What people should know

In January of 2013, Washington State law (RCW 19.27.530) required CO alarms to be installed in new residences and in existing rental properties. Owner-occupied single-family residences, legally occupied before July 26, 2009, are not required to have CO alarms until they are sold or when a building permit application for interior remodeling is submitted.

Homeowners should consider replacing all CO alarms that were installed in or before 2013. A CO alarm that signals that it’s at the end of its life should be replaced as well.

Renters should notify property managers or landlords immediately if their CO alarm is beeping every 30 seconds indicating its end-of-life. They should also know that intermittent beeping CO alarm is not reason to call 9-1-1.

A CO alarm that beeps continuously without stopping could indicate that carbon monoxide is present. If you your CO alarm is sounding continuously and you have signs of CO poisoning such as dizziness, headache, vomiting or flu like symptoms, find fresh air and call 9-1-1 immediately.

More information on carbon monoxide alarm requirements

State Building Code Council’s Carbon Monoxide Alarm page.

Seattle Fire Department’s CAM 5121 Carbon Monoxide Alarm Requirements in Residential Occupancies

What does a dying carbon monoxide alarm sound like?

Here's a simple guide: Smoke alarms alert you with three beeps in a row. Carbon monoxide alarms alert you with four beeps. A single chirp means the battery is low or the detector should be replaced.

How do I stop my carbon monoxide alarm from beeping at end of life?

Replace or Check the Battery Usually, the annoying beeping caused by a carbon monoxide detector is to alert you about a malfunctioning battery. If the old battery requires changing or it's slipped out of place, the unit will chirp. Try reinstalling the battery or replacing it, and then reset your device.

Do carbon monoxide detectors beep when they expire?

CO alarms have a life expectancy of around seven years. All CO alarms produced after August 1, 2009, have an end-of-life warning notification that alerts the resident that the alarm should be replaced. The CO alarm will beep every 30 seconds or display ERR or END.

What does it mean when First Alert carbon monoxide detector says end?

If your digital carbon monoxide alarm says “END” on the display, this means it has reached the end of its life and needs to be replaced. The alarm will also chirp 5 times per minute to let you know it's time for replacement.