Carbon monoxide sensors are vital safety components in your household, shielding you from lethal gases. When the alarm activates, performing a reset ceases the beeping and recommences carbon monoxide sensing to verify its functionality. Resetting your sensor is necessary only when the alarm triggers, and the process takes just a few seconds. Continue reading for comprehensive guidance on when and how to reset your carbon monoxide sensor.
Essential Information
- Press the Reset button located on the front of the carbon monoxide sensor to initiate a reset. Refer to your user manual for specific instructions.
- Utilize the Reset button whenever the alarm sounds or when replacing the batteries.
- If the alarm persists after resetting, evacuate everyone from the premises and contact emergency services immediately.
Procedure
Rebooting a Carbon Monoxide Detector

Depress the Reset button once. Your carbon monoxide alarm might feature a separate Test button or a combined “Test/Reset” button on its front panel. Press the button to reset the carbon monoxide detector and silence the alarm. Certain models may have an accompanying LED light near the button to indicate successful reset.
- Refer to the user manual for your specific carbon monoxide detector model, as reset instructions may differ. For instance, you may be required to hold the button down for 5–10 seconds to complete the reset process.
- Some carbon monoxide detectors reset automatically. After sounding for approximately 5–10 minutes, the alarm will deactivate on its own.
When to Reset a Carbon Monoxide Detector?

Reset the detector whenever the alarm is triggered. Resetting your detector stops the beeping and clears any recorded electronic data. Whether the alarm activates during an emergency, a test, or due to low battery, the Reset button will temporarily silence it.
- If the alarm reactivates within 5 minutes of resetting, it indicates a high level of carbon monoxide in the vicinity. Evacuate to fresh air immediately to avoid carbon monoxide poisoning.
Understanding Carbon Monoxide Detector Alerts

There’s a presence of carbon monoxide in the vicinity. Take every alarm seriously. Immediately evacuate everyone to fresh air and contact emergency services to determine the cause of the carbon monoxide detection.
- Familiarize yourself with CO leak indicators in case your detector malfunctions, such as yellow flames on appliances, window condensation, and flu-like symptoms.

The batteries are running low. When the batteries in your CO detector are low, a single-station carbon monoxide detector may emit beeps and flash an LED light. Replace the depleted batteries with a fresh pair. Typically, battery replacement is necessary once or twice a year.

Your detector has reached the end of its lifespan. Carbon monoxide detectors typically last around 5 years. If there's no emergency and you've already attempted battery replacement, persistent chirping may indicate the need for unit replacement. Install a new CO detector promptly to ensure safety.
- Your CO detector may also feature an LED light flashing alongside the sound. Consult the user manual to interpret the number of flashes and the light color.
Assessing a Carbon Monoxide Detector

Conduct a weekly test on your carbon monoxide alarm. Allocate a convenient time during your weekly schedule to promptly test your carbon monoxide detector's functionality. Regular testing allows for timely identification of battery replacement or unit replacement needs.

Hold down the Test button for 5–10 seconds. Some carbon monoxide detectors feature a separate Test button, while others have a combined Test/Reset button. Press and hold the button whenever the alarm is not active to initiate the test cycle.

Listen for 4 short beeps to confirm proper functioning of the alarm. The test alarm emits beeps similar to those during an actual emergency. Pay attention to the beeps and observe the LED light to ensure it flashes.
- Each model of carbon monoxide detector varies, so refer to the instructions for correct testing procedures.
- If your alarm does not beep, consider replacing the batteries.
Pointers
Cautions
- If the alarm sounds and you experience headaches, dizziness, or difficulty breathing, immediately move to fresh air to prevent carbon monoxide poisoning.
- Avoid searching for the source of a carbon monoxide leak if the alarm is activated. Contact emergency services to safely identify the cause.