What is the end on the Kidde carbon monoxide detector?

Author: Adrain Boehm MD  |  Last update: Friday, January 9, 2026

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. Learn more about CO Alarms: Where to Buy First Alert, Onelink, or BRK Brands Products.

What does end mean on a kidde carbon monoxide detector?

When the CO alarm displays an End. message, the alarm has reached the end-of-life. The alarm will emit a quick beep every 30 seconds.

What is the end display on a carbon monoxide detector?

CO alarm life span and end-of-life signal

CO alarms have a life expectancy of around 7 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.

Why does my carbon monoxide monitor say end?

It appears that your alarms might be approaching their expiration. Typically, carbon monoxide alarms such as those from First Alert are designed to last between 5-7 years. When they near this age, they often emit chirps or display an ``END'' or similar error code, which seems to be what you're experiencing.

What is the end of life signal on Kidde?

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, the unit has reached the end of its 7 or 10 year life.

The Secret Behind the END on Carbon Monoxide Detectors

What does a carbon monoxide detector sound like at the end of life?

When the detector is making chirping sounds every 30 seconds, this is not the same as a continuous siren. The chirping sound usually indicates the alarm is near its end of life and requires replacing. Carbon monoxide detectors have a seven-year lifespan. Replacing the battery does not stop this type of beeping.

How do you reset the end of life on a Kidde carbon monoxide alarm?

End-of-life- ERR will appear once the alarm has been active for its 7- or 10-year life to signal an end-of-life warning. Power Surge- If you think a power surge is the cause of the ERR message, press and hold the Test/Reset button for 5 seconds.

How to stop kidde end of life beeping?

The chirp will not stop until the unit is powered off. You'll know that it is an end-of-life warning and not a low battery warning because replacing the batteries will not stop the chirp. The chirp will stop only when the alarm is powered off.

What is the end of life of Kidde smoke detectors?

This alarm is acceptable for use in all residential applications where smoke alarms are required. After ten (10) years of cumulative power up, this unit will “chirp” two times every 30 seconds. This is an “operational end of life” feature which will indicate that it is time to replace the alarm.

How to tell if a carbon monoxide detector needs a new battery?

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 to silence end of life carbon monoxide alarm?

Silence feature: When CO reaches alarm levels the alarm will sound—repeating horn pattern: 4 beeps, a pause, 4 beeps, etc. Press and hold the Test/Silence button until the horn is silent. The initial Silence cycle will last approximately 4 minutes.

What is the life of a kidde carbon monoxide detector?

Kidde CO alarms have a proven life of seven to ten years, depending on the model type. Important Note! CO alarms do not detect the presence of CO when in end-of-life mode. Replace your CO alarms before the end-of-life warning.

How to tell if a carbon monoxide detector is working?

How to test your carbon monoxide detectors to ensure they are working properly? To test your carbon monoxide detectors, press and hold the test button on the alarm. The detector will sound 4 beeps, a pause, then 4 beeps for 5-6 seconds. Refer to the user manual for your specific model.

How do I know if my kidde carbon monoxide alarm is going off?

When the carbon monoxide alarm senses a dangerous level of CO gas, the unit will emit a loud alarm pattern. The alarm pattern is four short beeps – followed by five seconds of silence – followed by four short beeps.

What should my Kidde carbon monoxide detector read?

Low level: 50 PPM and less. Mid-level: Between 51 PPM and 100 PPM. High level: Greater than 101 PPM if no one is experiencing symptoms. Dangerous level: Greater than 101 PPM if someone is experiencing symptoms.

How do you silence a Kidde smoke and carbon monoxide alarm?

If the alarm is sounding, pressing the test/reset button will terminate the alarm. If the CO condition that caused the alert in the first place continues, the alarm will reactivate.

What does end mean on my carbon monoxide detector?

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.

What is the hush feature on Kidde carbon monoxide alarm?

The Hush® feature of most alarms provides the capability to temporarily lower the sensitivity of the smoke sensor for up to 10 minutes. This feature should be used only when a known alarm condition, such as smoke or heat from cooking, activates the alarm.

What can falsely set off a carbon monoxide detector?

Common causes of false alarms of carbon monoxide:
  • Close to cooking sources (10 feet minimum)
  • Close to sources of humidity (10-20 feet)
  • Near fireplaces.
  • Near water heaters.
  • Near furnaces.
  • Located in a poorly ventilated location like a garage, kitchen, or closet.

How do you turn off a low battery kidde carbon monoxide alarm?

Break through label with a screwdriver. Turn the screw to the “OFF” location. This will deactivate the alarm, stop the low battery chirp and render the alarm safe for disposal by draining the battery. NOTE: Turning off the alarm is permanent.

Will taking the battery out of a smoke detector stop the beeping?

Taking the battery out of a smoke alarm will not make it stop beeping. Even after the battery has died, the detector maintains a residual charge that will keep the chirp going for at least seven days.

What is the end message on Kidde?

When your alarm nears its end of life, it will let you know by beeping 2 times every 30 seconds. Digital models will also display the word "END". Knowing how to identify these sounds and what they mean is essential to keeping your home safe.

What is end of life on Kidde unit?

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.

What to do with an end of life carbon monoxide detector?

What is important is that when an end-of-life signal is sounded, the CO alarm must be replaced. This is true if the unit is a standalone CO alarm, or in a combination unit with a smoke alarm.

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