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Appliances around your home, such as fireplaces, boilers, and water heaters, can emit carbon monoxide if they don’t fully burn their fuel. Because carbon monoxide isn’t visible and doesn’t have a smell, you should install carbon monoxide detectors throughout your house to monitor the levels of this gas and improve your home safety. To learn about the best carbon monoxide detectors that can protect you and your family, read our review below.
Top 5 Carbon Monoxide Detectors
- Best Visual Alerts: First Alert Combination Smoke and Carbon Monoxide Detector
- Best Pack Options: Kidde Smoke & Carbon Monoxide Detector
- Best Plug-In Detector: Kidde Nighthawk Carbon Monoxide Detector
- Best Lifespan: X-Sense Smoke and Carbon Monoxide Detector
- Best Smart Detector: Google Nest Protect Smoke Detector and Carbon Monoxide Detector
Compare Top Carbon-Monoxide Detectors
| Product | Detection | Alert Type | Design | Warranty |
|---|---|---|---|---|
| First Alert Combination Smoke and Carbon Monoxide Detector | Smoke and carbon monoxide | Visual and auditory | Battery-powered | Seven years |
| Kidde Smoke & Carbon Monoxide Detector | Smoke and carbon monoxide | Auditory | Battery-powered | 10 years |
| Kidde Nighthawk Carbon Monoxide Detector | Carbon monoxide | Visual and auditory | Cord-operated with battery backup | 10 years |
| X-Sense Smoke and Carbon Monoxide Detector | Smoke and carbon monoxide | Visual and auditory | Battery-powered | 5 years |
| Google Nest Protect Smoke Detector and Carbon Monoxide Detector | Smoke and carbon monoxide | Visual and auditory | Battery-powered | 2 years |
| Product | Detection | Alert Type | Design | Warranty |
Best Visual Alerts: First Alert Combination Smoke and Carbon Monoxide Detector
First Alert Combination Smoke and Carbon Monoxide Detector
Pros and Cons
✔ Continues to work even if there’s a power outage because it’s battery-operated
✔ Uses an electrochemical sensor for carbon monoxide and a photoelectric sensor for smoke
✔ Has three types of beeps—one for detection, one for low battery, and one for end of life
✘ Doesn’t ship to New York residents
✘ Some customers received defective ones that died within a few months
What Customers Are Saying
Customer reviews we found said that this detector was easy to install, had a loud alarm, and offered a lot of features. Those who were disappointed with the product said that it malfunctioned after a few months of use.
Best Pack Options: Kidde Smoke & Carbon Monoxide Detector
Kidde Smoke & Carbon Monoxide Detector
Pros and Cons
✔ Has voice notifications
✔ Includes a battery backup
✔ Has photoelectric sensor technology
✘ Doesn’t have a digital display
✘ Some customers complained of false alarms
What Customers Are Saying
Customers praised this device’s low noise level, long-lasting battery and ease of installation. We also noted that those who didn’t enjoy their purchase said that they were missing parts, and others said they were not as durable as anticipated.
Best Plug-In Detector: Kidde Nighthawk Carbon Monoxide Detector
Kidde Nighthawk Carbon Monoxide Detector
Pros and Cons
✔ Has an LED display that gives you a reading of your room’s carbon monoxide level
✔ Features a test button to make sure that the detector is working
✔ Comes with a 10-year warranty
✘ Doesn’t detect smoke along with carbon monoxide like the other models in this review
✘ Some customers received faulty models that started beeping within days to warn them that the backup battery was dead
What Customers Are Saying
Our research showed that customers who enjoyed this carbon monoxide detector said that it was easy to install and provided peace of mind. However, some reviewers had difficulty utilizing the manufacturer’s limited warranty.
Best Lifespan: X-Sense Smoke and Carbon Monoxide Detector
X-Sense Smoke and Carbon Monoxide Detector
Pros and Cons
✔ Can be purchased in other packs with more than one detector
✔ Its digital display tells you the charge of the battery
✔ Has an LED light that turns green when it’s working and doesn’t detect carbon monoxide, yellow when it’s not working, and red when it detects carbon monoxide
✘ May be difficult to read the screen depending on how high your ceilings are
✘ Can go off even when there aren’t contaminants in the air
What Customers Are Saying
Most reviewers we found were satisfied with the detector, saying that it was well-made and a good value. A lot of customers appreciated the light indicator that was paired with the alarm. Those who were unsatisfied with their purchase said that mounting the device to a wall was difficult.
Best Smart Detector: Google Nest Protect Smoke Detector and Carbon Monoxide Detector
Google Nest Protect Smoke Detector and Carbon Monoxide Detector
Pros and Cons
✔ Available in battery-powered and hardwired versions
✔ Can silence the smoke alarm from the mobile app if there’s only a little smoke from cooking
✔ Lights up when you walk by it to help you see where you’re going
✘ Has a high price point
✘ Takes longer to set up because it requires connecting it to the internet and downloading an app
What Customers Are Saying
Several customers we found said that they loved the Amazon Alexa integration and motion detection of this device. We also noted that some of those who were unsatisfied with their purchase said that it was more difficult to install than basic devices because of the smartphone setup.
Buyer’s Guide
Not every carbon monoxide detector is the same. Here are a few features that we find vary from model to model to help you choose the best CO alarm for your needs.
Power Source
Carbon monoxide detectors are either battery-operated, plug-in, or hardwired.
- Battery: These detectors work even if your power goes out because they run on standard AA batteries or AAA batteries. However, the batteries only last about a year before they need to be replaced. The device will usually chirp to tell you when you have low battery. Occasionally, battery-operated detectors will use lithium batteries, which don’t need to be changed since they last for the entire lifespan of the detector.
- Plug-in: Plug-in models plug into an outlet. They usually come with a battery backup to continue working during a power outage.
- Hardwired: This type of detector is hardwired to your home’s circuitry. Similar to plug-in models, hardwired carbon monoxide models don’t work during power outages unless they have a battery backup.
Function
Most smoke alarms detect more than just carbon monoxide. The most common second function you’ll find in a carbon monoxide detector is smoke and fire detection, but you can also find devices that detect natural gas.
Display
Some detectors have a digital display that allows you to determine if there’s any carbon monoxide in your home, even if it’s a small amount that won’t hurt you. If your carbon monoxide detector doesn’t have a digital display, it’ll likely beep when the level of carbon monoxide in the air reaches a dangerous level.
Alert Volume
The CO detector should be loud enough to wake you up and to be heard from every part of the home, particularly in sleeping areas Most detectors have an alarm that’s at least 85 decibels. However, the alarm will be quieter from across the home, which is why it’s important to have more than one installed. Some alarms also include voice alerts notifications that describe what the specific alarm is.
Interconnectivity
As previously mentioned, you’ll need to install several carbon monoxide detectors in your home if it’s relatively large. This will help you hear the alarm from anywhere in your home and ensure that you’re getting accurate carbon monoxide readings throughout your home. If you purchase several of the same model, you’ll be able to connect the devices to ensure that if one detects carbon monoxide, all of them will beep to alert you.
Lifespan
The sensors in your detector will typically wear out after five to 10 years. Consider replacing your device around this timeframe.
What Could Cause a Carbon Monoxide Leak?
There are numerous things in and around your home that could lead to a carbon monoxide leak, making it even more essential to stay well-equipped with a high-quality, working carbon monoxide detector. Here are some of the biggest reasons why a carbon monoxide leak could occur.
- Faulty or poorly maintained appliances: Gas-powered furnaces, water heaters, stoves, ovens, fireplaces, and other fuel-burning appliances can release carbon monoxide if they are malfunctioning or not properly maintained. The most frequent cause is due to issues with ventilation, burner problems, or blocked exhaust flues.
- Inadequate ventilation: Proper ventilation is crucial for removing combustion byproducts, including carbon monoxide, from indoor spaces. If a home’s ventilation system is not functioning correctly or if there are obstructions in vents, CO can build up indoors.
- Cracked or damaged heat exchangers: In gas furnaces, heat exchangers are designed to separate combustion gases from the heated air circulated through the home. If the heat exchanger is cracked or damaged, it can allow carbon monoxide to mix with the indoor air.
- Blocked chimneys or flues: Chimneys and flues are responsible for venting exhaust gases safely to the outside of your home. If they become blocked or clogged with debris, it can cause a backdraft, allowing carbon monoxide to enter the living spaces.
- Using outdoor equipment inside: Using generators, grills, or other gasoline-powered equipment indoors or in enclosed spaces can produce high levels of carbon monoxide. These items should always be used outdoors in well-ventilated areas.
- Vehicle exhaust in attached garages: When a vehicle is left running in an attached garage, carbon monoxide can seep into the living areas of the house. It is essential to open the garage door before starting the car and to avoid running vehicles inside the garage.
Frequently Asked Questions
Who is at risk of carbon monoxide poisoning?
If you have a carbon monoxide leak in your home, infants, young children, the elderly, and people with chronic heart disease, anemia, or respiratory problems are at a higher risk of carbon monoxide poisoning.
What are the symptoms of carbon monoxide poisoning?
Symptoms of carbon monoxide poisoning look similar to those of the flu. You may experience the following if you’re exposed to high co levels.
- Dizziness
- Weakness
- Headache
- Upset stomach
- Vomiting
- Chest pain
- Confusion/disorientation
Am I supposed to test my carbon monoxide detector?
Yes. You should test your detector at least once a month. Most models will have a button on them that you can press. When you press that button, the device should sound the same alarm that would go off if carbon monoxide is detected.
Where should I put my carbon monoxide detectors?
You should have a carbon monoxide detector on every floor of your home and 15-20 feet from your furnace or another fuel-burning heat source. If you want more protection, you can place a carbon monoxide detector outside of every bedroom.
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