Best Carbon Monoxide Detector of 2020

In Home Security by Christy

Every year, about 170 people die in the US due to carbon monoxide poisoning associated with generators, furnaces, water heaters, fireplaces, and other fuel-burning consumer products!

That’s why every household is advised to install at least one carbon monoxide detector on every floor. When the device detects a dangerous level of carbon monoxide (CO), it alerts you and your loved ones about the danger so you can evacuate right away.

Becoming an expert on the available products could take an hour of reading!

Instead, I’ve done the research for you and put together the best carbon monoxide detectors available to help you make the right decision for your situation.

Here’s what you’ll learn:

What carbon monoxide level is dangerous to my health?

ProductProsConsRatingPrice
Kidde KN-COPP-3 Nighthawk- Easy to install
- Comes with a digital display
- Comes with a limited warranty of 10 years
- Stores the highest CO reading detected to monitor if levels spiked
- Mounting hardware is customizable
- Users claim that the sensor life is less than the advertised 10 years
- The unit will not run without a backup battery installed even if it is AC-powered
- Users cannot snooze false alarms
4.5/5$27
First Alert CO605 Carbon Monoxide Plug-In Alarm- Easy installation
- Test-silence button is easy to use
- Comes with a 7-year limited warranty
- Unit is automatically backed-up with a battery
- Loud 85-decibel alarm
- Uses electrochemical sensors
- Unit is shipped with cheap batteries
- Doesn’t have a digital display
4.5/5$19.49
Nest Protect Smoke & Carbon Monoxide Alarm- Interconnectivity with other Nest products
- Full control using a mobile app
- Issues gentle warning prior to sending a full alarm
- Modern and elegant design
- Self-test and voice alert capabilities
- Expensive
- Upgrade doesn’t show much difference with the first-generation Nest Protect
- Wireless connection required to control using a mobile app
4.3/5$199
Sensorcon Industrial PRO Carbon Monoxide Gas Monitor- Rugged, waterproof design
- Small, light-weight, and easy to carry
- Reading is extremely accurate
- Fully battery-operated using CR123A batteries
- Short battery life
- Needs calibration by a professional at least every 6 months
4.3/5$159
Ring Alarm CO and Smoke Listener- Small, light and portable
- Fully battery-operated
- Works with Amazon Alexa
- Can work with other CO or smoke detectors, regardless of the brand
- Option to avail 24/7 professional monitoring at $10 per month or $100 a year
- Unit is over-priced given it’s only a listener
- Can only be used with existing CO and smoke alarms not more than 10 years old
- No IFFT integration
- Requires a 3-minute cooldown period when the alarm is dismissed via the app
4/5$34.99

Comparison of Carbon Monoxide Detectors:

ProductKidde KN-COPP-3 NighthawkFirst Alert CO605 Carbon Monoxide Plug-In AlarmNest Protect Smoke & Carbon Monoxide AlarmSensorcon Industrial PRO Carbon Monoxide Gas MonitorRing Alarm CO and Smoke Listener
Price$27$19.49$199$159$34.99
CO and Smoke DetectionNoNoYesNoNo
Power SourceAC-poweredAC-poweredWired or battery operatedBattery operatedBattery operated
Digital DisplayYesYesNoneYesNone
Smart Home IntegrationNoneNoneYesNoneYes (Ring Products)

What carbon monoxide level is dangerous to my health?

On average, exposure to CO concentration at approximately 1 - 70 ppm may not cause obvious symptoms to healthy individuals but for people who have heart problems, the symptoms can include chest pain. Pregnant women, young children, and babies are also more vulnerable to this carbon monoxide level. 

If the CO level continues to increase and remain above 70 ppm, symptoms such as headache, nausea, and fatigue will start to show. When CO concentrations are above 150 to 200 ppm, it is possible for a healthy person to experience disorientation, unconsciousness, and death.

Types of Carbon Monoxide Sensors

Before you buy a carbon monoxide detector, it is important to know the four commonly used sensors so that you can easily decide which carbon monoxide detector is best for you.

Biomimetic sensor

This type of sensor detects carbon monoxide through a combined color-changing solution or gel-like chemical. Carbon monoxide detectors that use biomimetic sensors can last up to three years.

Metal oxide semiconductor

A metal oxide semiconductor is a sensor designed with wired circuits to detect different levels of carbon monoxide. Detectors based on metal oxide semiconductors generally have a life span of up to 10 years.

Electrochemical sensor

Electrochemical sensors are known as the best type of sensor to monitor carbon monoxide for home. It works by generating current that can used to detect various carbon monoxide levels. Electrochemical sensors have a longer life span compared to metal oxide semiconductor and biomimetic sensors.

Optochemical sensor

Optochemical sensors are cheaper compared to other carbon monoxide sensors since they only need to detect the presence of carbon monoxide. It uses a pad that changes color when the poisonous gas is present. Since it cannot monitor the various levels of carbon monoxide present in your home, it can only offer limited protection. 

Important Features to Look For

When choosing a CO detector, you should look for these features:

Ease of Use

There’s nothing more inconvenient than a device that’s difficult to install and has complicated displays! You don’t want to spend an enormous amount of time figuring out how the buttons work or difficulty in opening/ closing the battery compartment. To save you from the trouble, check our notes and choose a CO detector that is easy to install and use.

Connectivity

Nowadays, wireless CO detectors with alarm connectivity features are available.  They allow you to install multiple detectors on the different parts of your home and have them connected together. If you have a large home with multiple floors, these wireless CO detectors would be more beneficial to you. They are synced together so that it sounds an alarm when one of the detectors detects a dangerous level of CO.


As an alternative, some security cameras with audio capability listen for alarms and give you notifications on your phone when one goes off.  The iSmartAlarm Spot is one with that feature. Check out our detailed review of the Spot if you want alerts while you’re away from home and decide to buy a cheaper carbon monoxide detector without WiFi, Z-Wave, or Zigbee connectivity.

Power Source

Carbon monoxide detectors can be wireless (battery operated) or wired (connected to the AC outlet for power). Depending on your preferences, each may have its own advantages as well as disadvantages. Battery-operated CO detectors are generally cheaper and more portable than wired CO detectors. 

But, changing batteries in the middle of the night really stinks (make sure you always have spare batteries at home)! On the other hand, hardwired CO detectors require less maintenance but are more costly and require an electrician (or an industrious homeowner ;)) to properly install them.

Battery Backup

Depending on the brand, carbon monoxide detectors are powered either through batteries or electricity from the AC outlet. Some detectors also have both so that when there is power interruption, the battery can be used as a backup. 

If you want to be protected if the power goes out, it’s best to have backup power for your detectors.

Sensor Life

When choosing a carbon monoxide detector, make sure that you also check the date of manufacture. CO sensors are sensitive and can wear out over time, so it’s best to use a sensor that is close to the date of manufacture. You don’t want to pick up a sensor with a 3 year life that’s been sitting on the shelf for over a year!

Digital Display

CO detectors with digital displays are convenient if you want to be constantly updated on the CO concentrations in your home. The digital display shows the real-time CO concentration in parts per million (PPM) and may even include temperature and humidity readings (depending on the brand pr manufacturer). 

On average, a carbon monoxide concentration of 70 PPM is not safe for a normal person while young children, pregnant women and people with heart problems should not be exposed to CO concentrations higher than 30 PPM.

Combination / Stand Alone Unit

Carbon monoxide detectors can be available as a stand-alone unit or a combination of CO and smoke detectors. CO detectors combined with smoke detection features can be more expensive but worth the investment in the long run since they perform two functions in one package, saving you money and time during installation and setup.

Price

While it’s true that having a unit with lots of features can be beneficial, it can also be a costly investment. If you prefer a CO detector that has all the basic functions to protect your home, you can expect it to be around $25 or more. In a large home, you may need to add more detectors increasing the cost substantially.

Our Best Carbon Monoxide Detector For Houses and Apartments

Kidde KN-COPP-3 Nighthawk

Kidde

Price: $27
Rate: 4.5/5

Pros:

  • Easy to install
  • Comes with a digital display
  • Comes with a limited warranty of 10 years
  • Stores the highest CO reading detected to monitor if levels spiked
  • Mounting hardware is customizable

Cons:

  • Some users claim that the sensor life is less than the advertised 10 years
  • The unit will not run without a backup battery installed even if it is AC-powered
  • Users cannot snooze false alarms

If you’re looking for a CO detector that’s affordable, effective at monitoring CO levels, and installs easily, then the Kidde KN-COPP-3 Nighthawk could be the perfect device to suit your needs. 

This detector is available in a small and inconspicuous design which you can plug easily in an AC outlet. It comes with a 9V battery backup to keep your home protected even during a power failure. The device is designed with a digital display so you can easily read the CO levels updated every 15 seconds. The Kidde KN-COPP-3 Nighthawk also features a “peak level” memory so you will know the highest CO level since its last reset. 

Kidde claims a sensor life of 10 years and backs it up with a 10-year limited warranty.

First Alert CO605 Carbon Monoxide Plug-In Alarm

FirstAlert

Price: $19.49
Rate: 4.5/5

Pros:

  • Easy installation
  • Test-silence button is easy to use
  • Comes with a 7-year limited warranty
  • Unit is automatically backed-up with a battery
  • Loud 85-decibel alarm
  • Uses electrochemical sensors

Cons:

  • Unit is shipped with cheap batteries
  • Doesn’t have a digital display

The First Alert CO605 is popular for its simplicity and convenience. It offers a backup battery to ensure continuous monitoring as well as a mute button to silence a false alarm. You can also test the alarm by just pressing one button. Since it’s designed with an electrochemical sensor, you are assured of an accurate reading compared to other CO detectors. 

When the unit detects a dangerous level of CO, it gives off an alarm at 85 dB. The First Alert CO605 also comes with an end of life warning to tell you when the device needs to be replaced.

Nest Protect Smoke & Carbon Monoxide Alarm

Nest

Price: $199
Rate: 4.3/5

Pros:

  • Interconnectivity with other Nest products
  • Full control using a mobile app
  • Issues gentle warning prior to sending a full alarm
  • Modern and elegant design
  • Self-test and voice alert capabilities

Cons:

  • Expensive
  • Upgrade doesn’t show much difference with the first-generation Nest Protect
  • Wireless connection required to control using a mobile app

Compared to the first generation of Nest Protect, the recent upgrade has more stylish design while being effective at monitoring CO levels and smoke. The new compact design includes in-app testing as well as alarm silencing options which is quite convenient in case you’ve accidentally triggered the alarm while using your fireplace or cooking in the kitchen. Moreover, the Nest Protect can be easily paired with other Nest devices such as cameras and thermostats so you can create a complete home automation / alarm system. Nest (Google) claims that the device can last up to 10 years, and it’s available in wired or wireless versions with AA battery backup.

Sensorcon Industrial PRO Carbon Monoxide Gas Monitor

Sensorcon

Price: $159
Rate: 4.3/5

Pros:

  • Rugged and waterproof design
  • Small, light-weight, and easy to carry
  • Reading is extremely accurate
  • Fully battery-operated using CR123A batteries

Cons:

  • Short battery life
  • Needs calibration by a professional at least every 6 months

People with health problems or working in an environment with potentially dangerous levels of carbon monoxide will benefit from using the Sensorcon Industrial PRO. This device offers highly accurate readings up to 2,000 ppm and displays values in a programmable, real-time digital display. Since it is designed to be portable, it is light-weight (around 4 ounces) and you can easily carry or wear it using an alligator clip or lanyard loop. You can set the device in various alarm modes to customize the alerts.

Ring Alarm Carbon Monoxide and Smoke Listener

RingCO

Price: $34.99
Rate: 4/5

Pros:

  • Small, light and portable
  • Fully battery-operated
  • Works with Amazon Alexa
  • Can work with other CO or smoke detectors, regardless of the brand
  • Option to pay for 24/7 professional monitoring at $10 per month or $100 a year 

Cons:

  • Unit is over-priced given it’s only a listener
  • Can only be used with existing CO and smoke alarms not more than 10 years old
  • No IFFT integration
  • Requires a 3-minute cooldown period when the alarm is dismissed via the app

If you have an existing CO and smoke alarm at home that doesn’t connect to Wifi and is not more than 10 years old, then you can add the Ring Alarm CO and Smoke Listener to notify you when the smoke and CO alarm goes off. This is very useful to monitor your home while you’re away. The device can be used with the Ring app as well as the Ring Alarm Security Kit so that you can receive maintenance or alert notifications through your smartphone.

Best Travel or Portable Carbon Monoxide Detector

When it comes to portability, the Sensorcon Industrial PRO is your best option due to its light-weight, compact design, and accurate readings. People who have health problems or are working in an environment that may expose them to dangerous levels of CO can find this product very useful.

Best RV Carbon Monoxide Detector

The Kidde KN-COPP-3 Nighthawk is ideal for monitoring CO levels in any contained areas such as your home, garage, or RV. The small and inconspicuous packaging of Kidde makes it convenient to use and placed anywhere with an AC outlet. You can easily monitor peak levels of CO as well as its real-time reading through its digital display.

Best Combination Carbon Monoxide and Gas Detector

When it comes to detecting carbon monoxide and gas, the First Alert CO605 is the best option. It comes with an electrochemical sensor that gives the most accurate reading, keeping you updated in real-time.

Best Combination Smoke and Carbon Monoxide Detector

Overall, the Nest Protect Smoke & Carbon Monoxide Alarm offers the best features when it comes to monitoring smoke and carbon monoxide in your home, garage, or RV. Although it comes with an expensive price tag, the device is definitely worth the investment, in the long run, to give your family the best protection.

Frequently Asked Questions

How to Test a Carbon Monoxide Detector

For most carbon monoxide detectors, you can test your CO detector by pressing the “test” button and listening for  two beeps. If the device doesn’t produce the beeping noise, then it means you need to replace the batteries or the unit itself.

What’s the Best Location for a Carbon Monoxide Detector?

It is highly recommended to place a CO detector on every floor of your home. To install, make sure that the device is about 5 feet above the ground to get the best reading. It’s also recommended that you place CO detectors near a bedroom so that everyone can hear the alarm when the CO level is high at night.

If you have a gas furnace or heater that produces carbon monoxide, you may want to consider mounting the unit near it too.

Do I need a Low-Level Carbon Monoxide Detector?

Although the UL standard doesn’t include low levels of CO (because they believe that only high levels matter - around 70 ppm and up) it doesn’t mean it’s completely harmless. High-risk individuals such as pregnant women, babies, young children, and people who have health problems need maximum protection from this deadly gas. Having a low-level carbon monoxide detector can help a lot in protecting your family, especially those who are vulnerable.

The Sensorcon Industrial PRO Carbon Monoxide Gas Monitor will alert on levels less than 70 ppm.

Which carbon monoxide detectors can I connect to my home security system?

Carbon monoxide alarms such as the Nest Protect and Ring Alarm CO and Smoke Listener can be integrated into a home security system. However, make sure that the devices are compatible before you buy them.  Products like the Ring only work with Ring products.

Wrapping It Up

Carbon monoxide is a silent threat that can be present in our homes. Monitoring the CO levels and taking preventive measures ensures that you and your loved ones are protected. Understanding the dangers of this gas helps you choose the right CO detector for your home.

That’s it for our best carbon monoxide detector review this year! We hope you find this post helpful. If you have any questions or suggestions, please comment down below!