According to the National Fire Protection Association (NFPA), local fire departments respond to an average of 79,600 carbon monoxide incidents in a year. Add to that the 91,400 carbon monoxide alarm malfunctions and the 68,000 false alarms that occur in the same period. Plus, the CDC (Center for Disease Control and Prevention) says about 400 people die from unintentional CO exposure not linked to fires in the US each year. 

Carbon monoxide detectors are designed to beep when they sense dangerous carbon monoxide levels. However, they sometimes beep due to other reasons. Find out why your carbon monoxide detector is beeping and what to do when it does. 

What Is a Carbon Monoxide Detector? 

A carbon monoxide detector helps protect you from carbon monoxide poisoning. Carbon monoxide (CO) is a colorless, odorless, and tasteless gas produced when carbon-based fuels, like gas, wood, or propane, burn incompletely. It's harmless in small amounts but deadly in higher concentrations.

You can't detect carbon monoxide with your senses, so a detector is crucial. The device works by measuring the amount of CO in the air. When the concentration reaches a dangerous level, the detector sets off an alarm, giving you enough time to take action.

Carbon monoxide poisoning can cause symptoms like dizziness, headache, nausea, chest pain, and confusion. These signs are similar to the flu, which makes it harder to recognize. In extreme cases, exposure can lead to unconsciousness or death.

A carbon monoxide detector is different from a smoke detector, though both warn you of hazards. A smoke detector senses smoke from a fire, while a CO detector senses carbon monoxide. Both are must-haves in your home.

How Does a Carbon Monoxide Detector Work?

A carbon monoxide detector works by measuring the amount of carbon monoxide (CO) in the air and sounding an alarm if the levels get dangerous. Since carbon monoxide is colorless, odorless, and tasteless, you can’t detect it yourself. The detector helps by using different technologies to sense the gas.

According to the National Institute of Standards and Technology (NIST), the most common type uses electrochemical sensors. These sensors have electrodes submerged in a liquid that conducts electricity. When CO enters the sensor, a chemical reaction occurs. The reaction then changes the electrical current. The amount of change tells the detector how much CO is present.

Another type uses metal oxide sensors. These sensors rely on a special chip that lowers its electrical resistance when CO is present. The higher the CO level, the more the resistance changes. The detector can measure that change.

Some detectors mimic the way our blood reacts to carbon monoxide. Just like CO can bind with hemoglobin in our blood, some detectors use a gel that changes color when it absorbs CO. A light sensor tracks the color change and determines how much CO is around.

No matter the technology, carbon monoxide detectors help keep you safe by warning you early. They alert you before dangerous symptoms like headaches or dizziness start, giving you enough time to evacuate.

Why Is My Carbon Monoxide Detector Beeping? 

A carbon monoxide detector beeps for many reasons, including dangerous CO levels and low batteries. Here are some of the most common reasons why your CO detector is beeping: 

1. Carbon Monoxide 

The most serious reason for a beeping carbon monoxide detector is a high carbon monoxide level. This is dangerous, as CO is a deadly colorless, odorless, and tasteless gas. If your detector is beeping because of high CO levels, leave the area immediately and get fresh air. CO poisoning can cause symptoms like dizziness, headaches, and nausea. It can also lead to unconsciousness or death if left unchecked. So, take this beeping seriously and get out fast. Once you’re safe, call emergency services and get the issue checked out. Make sure no one re-enters the house or building until the professionals say it’s safe. 

2. Low Battery

Another common reason why a carbon monoxide detector beeps is a low battery. If this is the case, you can stop the beeping by changing the battery. It’s a simple fix, but make sure to do it right away. If you ignore the low battery warning, the detector might stop working when you need it most. Some detectors also show a low battery indicator, so check the display. Experts also recommend replacing your battery at least once a year or as recommended by the manufacturer.

3. End of Life

Carbon monoxide detectors don’t last forever. Most of them need to be replaced every five to seven years. As they get close to the end of their life, they’ll beep to let you know it’s time for a replacement. Check how old your detector is if your unit beeps without detecting carbon monoxide. If it’s close to or past its expiration date, replace it. This is crucial because an old detector may fail to warn you in an emergency. CO detectors’ lifespans also vary, so check the manufacturer’s guidelines for the exact replacement period for your unit. 

4. Malfunction 

Carbon monoxide detectors might sometimes beep because of a malfunction or error. If the sensor is faulty, your unit might start beeping. Some detectors will show an error code on the display or make a different type of noise to indicate a problem. If the beeping continues and you can’t find an obvious cause, try resetting the detector or consult the user manual for troubleshooting steps. In some cases, you might need to replace the detector. 

5. Power Issues

Is your CO detector wired into your home’s electrical system? If yes, it might beep if there’s a power issue. This could happen after a power surge, a blackout, or if the circuit breaker trips. The beeping tells you the unit is not getting enough power. If this happens, check the power source and make sure everything is connected properly. Once the power issue is resolved, the beeping should stop. If the problem continues, call an electrician to check the wiring.

What Do Carbon Monoxide Beeps Mean?

Carbon monoxide detector beeps can vary depending on the unit. Whether it's a series of short beeps or a continuous alarm, knowing what they mean helps you stay safe. 

Continuous, Loud Beeps

A continuous alarm (often a repeating four-beep pattern) means your detector has sensed high levels of carbon monoxide in the air. This is a serious emergency, so evacuate the premises and get fresh air immediately.  

One Beep Every Minute

A carbon monoxide detector that beeps once every minute usually indicates a low battery. This is an easy fix—simply replace the battery right away. Even if your detector is plugged into the wall, the battery acts as a backup, so don’t skip this step.

30-Second Beeps 

Your unit might beep twice every 30 seconds when it reaches the end of its life. This is a signal that it can’t detect carbon monoxide accurately anymore. Most detectors last five to seven years, so keep track of when you bought yours.

Three Beeps 

If your detector is beeping thrice in a row every five to 15 minutes, it’s likely malfunctioning. This means the sensor or the device itself is faulty. It’s best to replace the detector if this happens. 

Random Beeps

Intermittent or random beeps might indicate a malfunction or error in the unit. Some detectors display error codes, so refer to the manual to know exactly what they mean.

One Long Continuous Beep

A long, continuous beep might mean your unit has been tampered with or unplugged. This sound could also indicate the device is not functioning properly. Check to see if it’s still plugged and working properly. If the problem persists, call a professional to inspect your unit. 

What Should I Do if My Carbon Monoxide Detector Is Beeping?

Never ignore your beeping carbon monoxide detector. Act fast even if you think it’s a false alarm or a low battery.  Here’s what to do if your CO detector goes off: 

1. Leave the Building Immediately

If the alarm goes off and you suspect a carbon monoxide leak, don’t wait to figure out what’s going on. If anyone in your household shows carbon monoxide poisoning symptoms, get out and get them fresh air immediately. 

High levels of carbon monoxide can cause serious health problems, including brain damage. The sooner you get fresh air, the better. Don’t forget your pets since they’re also affected by CO as much as humans.

2. Call Emergency Services

Call 911 or your local fire department once you’re safe. Let them know you suspect a carbon monoxide leak. Emergency services will check the levels of carbon monoxide in your home and take action. Don’t re-enter even if someone is still inside the building. Let emergency responders know someone’s inside instead. 

3. Inspect Your Detector 

Immediately inspect your unit if it beeps for any reason other than detecting CO. Try replacing the battery, checking the power source, and the like. If fixing the issue stops the beeping, you're good to go. But if the problem persists, call a technician. 

4. Find Out if There’s a False Alarm

Your carbon monoxide detector can sometimes go off due to something harmless, like being too close to a gas stove or fireplace. Fuel-burning appliances release small amounts of CO. If your detector is too close, a false alarm might occur. Prevent this by placing your detectors within 10 feet of fuel-burning appliances.

5. Reset the Detector

Once you’re safe outside or have dealt with non-CO issues, reset your detector. Doing this will stop the beeping and make sure the device can monitor CO levels going forward.

Look for the reset button on the detector. Hold it down for about 15  seconds, then release it. Your detector should stop beeping, and the LED lights should blink or reset. You can reset smart detectors using an app.

6.  Replace Your Carbon Monoxide Detector 

Is your detector old? It might be time to replace it. Most carbon monoxide detectors last for five to seven years. Check the expiration date on the unit and replace it if needed. Even if it seems to work, an expired carbon monoxide detector won’t work as well as a new one.

7. Get a Professional Inspection

Ask a professional to inspect your home or building after the emergency. It’s crucial to figure out what caused the leak if you’ve had one. Common sources of CO leaks include:

• Gas appliances
• Chimneys 
• Fireplaces 
• Generators 
• Boilers 

Take note that CO leaks and poisoning are more common during the winter. It’s because homes are sealed tight against the cold. Make sure your appliances and heating systems are maintained properly to prevent leaks in the future.

What Does a Carbon Monoxide Detector Sound Like When It Detects Carbon Monoxide?

What a carbon monoxide detector sounds like when it detects carbon monoxide depends on the unit. A CO detector usually sounds a loud, continuous alarm in a repeating four-beep pattern. This sound is meant to get your attention immediately. However, not all carbon monoxide detectors sound like this when they detect dangerous CO levels. Always consult your manual to see exactly what your unit will sound like when it detects carbon monoxide. 

Will a Carbon Monoxide Detector Beep if the Battery Is Low?

Yes, a carbon monoxide detector will beep if the battery is low. While the exact beeping pattern depends on the unit, many CO detectors beep once every minute to indicate a low battery. Fortunately, this issue is easy to fix. Just replace the battery as soon as possible, and your detector’s good to go. Experts recommend replacing the battery at least once a year or as recommended by the manufacturer.

Can Anything Else Trigger a Carbon Monoxide Detector?

Yes, other things can trigger a carbon monoxide detector besides detecting the gas. These include low batteries, old age, malfunction, and power issues. Check and fix your unit immediately if it gets triggered by these problems. 

Conclusion

Carbon monoxide detectors are made to detect dangerous CO levels. However, they sometimes beep for other reasons. Knowing why your carbon monoxide detector beeps helps you take the right action and keep your loved ones safe. Whether it's carbon monoxide, a low battery, an outdated unit, a malfunction, or a power issue, never ignore your detector. 

While carbon monoxide detectors are a must, they are just one part of the equation. Having fire prevention tools like fire blankets and fire sprays is a must, too. CO detectors and fire safety tools work together to make sure you're ready for any emergency.