The 10 Best Carbon Monoxide Detectors

Sara Mandeed
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While carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is lethal to humans and animals, you may be surprised to learn that there are families who simply do not realize that they have a carbon monoxide problem in their home.

In fact, according to the Centers for Disease and Control and Prevention, carbon monoxide poisoning is the leading cause of unintentional poisoning deaths in the United States, killing about 500 people every year.

Because CO cannot be seen, smelled, or tasted, it is important that you have proper detection equipment in place for your home.

Obviously, if you can smell burning or see smoke, you know that something is burning, but if you are not a fire alarm person, you may not think to check if your CO levels are high.

You can purchase carbon monoxide detectors which can be installed to notify you via alarm if there is an elevated level of carbon monoxide in your home.

In fact, carbon monoxide detectors are required by most states and municipalities to be installed in all new homes, and many also want them to be installed in existing homes.

We have compared a lot of different CO detectors, and below are the top 10 best carbon monoxide detectors based on a wide range of factors like ease of use, effectiveness, energy efficiency, and features.

NameCategoryProduct
First Alert CO605 Plug-In Battery Backup CO AlarmBest OverallFirst Alert CO605 Plug-In Battery Backup CO Alarm
Kidde Carbon Monoxide Alarm DetectorBudget PickKidde Carbon Monoxide Alarm Detector
Google S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide DetectorUpgrade PickGoogle S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide Detector

1. First Alert CO605 Plug-In Battery Backup CO Alarm

Our rating: 9 / 10

First Alert CO605 Plug-In Battery Backup CO Alarm

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Pros:

  • Easy set-up
  • Battery backup for power outages
  • Loud and clear alarm
  • Digital display with backlight
  • Carbon monoxide is highly odorless and colorless
  • Eliminates the need for replacement batteries
  • Test button for user check

The First Alert CO605 is one of the best carbon monoxide detectors that you can pop into your home these days. Unlike other entry-level detectors that are limited to power cut backup, this thing comes with an internal lithium battery which lasts 5 years. It also gives you a choice between buying the 8-year limited warranty or the 10-year limited warranty. That’s a pretty sweet deal if you ask us.

Let’s talk about the design for a second. At 3.92 x 3.78 x 9.13 (in), this thing is compact, and it’s designed to fit into any ceiling outlet. These LEDs will keep their shine for up to ten years, and they’re guaranteed to never burn out. However, they do not turn off automatically, so you may want to do that manually once in a while to extend the battery life even further.

The battery backup is a critical feature, especially since CO poisoning is extremely dangerous.

2. First Alert Smoke Detector and Carbon Monoxide Detector Alarm

Our rating: 9 / 10

First Alert Smoke Detector and Carbon Monoxide Detector Alarm

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Pros:

  • Easy to install
  • Backlit digital display
  • 180-degree swivel-out hush feature
  • Long battery life
  • Easy to mount
  • Long effective range of detection
  • Can be used with AAA batteries
  • Can be mounted high up
  • Accurate readings

Cons:

  • Last-meets zero readings can be inaccurate
  • Display highly visible
  • Can be too sensitive
  • Digital display lacking a backlight

The First Alert Smoke Detector features a backlit digital display that is easy to read in low light levels. It has a hush feature that is conveniently angled at 180 degrees so that when not in use, it can be swiveled out and won’t be bothering or wakening you.

The alarm runs on power, and you can use either alkaline batteries or lithium batteries. The lithium batteries will last significantly longer compared to alkaline batteries. One of the many features that customers liked was that it is very easy to mount and can be mounted high up.

The alarm measures 4.4 x 4.4 x 1.3 inches and weighs in at 5.6 ounces – making it compact enough to be easily mounted on almost any surface. Consequently, it’s great for detecting both smoke and carbon monoxide.

3. Kidde Carbon Monoxide Alarm Detector

Our rating: 9 / 10

Kidde Carbon Monoxide Alarm Detector

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Pros:

  • Easy to install
  • Easy to operate
  • Loud alarm
  • Real-time display
  • Battery operated
  • Long battery life
  • Uses electrochemical technology to detect the presence of carbon monoxide
  • Can be used as a backup detector
  • Dark smoke, carbon monoxide can’t hide from you

Cons:

  • If batteries are missing when CO levels are high, the detector won’t chirp to alert you that the batteries need to be changed
  • Basic design/almost resembles a toy

If you’re looking for a solid carbon monoxide detector that’s going to get the job done without trading off on the features, you might want to consider this option from Kidde. Considering it’s one of the cheapest detectors on this list, it offers a lot of value for your money.

The Kidde detector may look basic, but don’t be fooled by its seemingly simplistic design. In fact, the electronic sensor is quite effective in detecting the presence of carbon monoxide in your home and is arguably one of the most sensitive that we’ve seen thus far.

4. Kidde 21026043 Battery-Operated(Not Hardwired) Combination Smoke/Carbon Monoxide Alarm

Our rating: 9 / 10

Kidde 21026043 Battery-Operated(Not Hardwired) Combination Smoke/Carbon Monoxide Alarm

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Pros:

  • Plug in-device
  • 8 year lithium battery included
  • Easy to install
  • Hourly hush feature
  • Battery backup
  • High sensitivity smoke sensor
  • Loud alarm
  • Battery failure and Tamper alerts
  • Voice warning feature

Cons:

  • No near-fire or CO2 detection
  • Doesn’t include a long term data management system
  • Doesn’t operate on all Nationalcodes
  • The alarm may go off for no reason

It is important to acquire the correct home smoke alarms to make you and your family safer. Most detectors should be hardwired; however, some battery operated devices are also available. Our top choice is well-priced, easy to use, and alerts you of both smoke and CO alarms.

This Kidde Battery-Operated Smoke/Carbon Monoxide Alarm with Voice Warning includes a voice warning system so you will know if there is an emergency. It features a silent alarm for testing the alarm and a hush button which silences the alarm if you are not in trouble.

5. Kidde Nighthawk Plug-In AC/DC Carbon Monoxide Alarm Detector

Our rating: 9 / 10

Kidde Nighthawk Plug-In AC/DC Carbon Monoxide Alarm Detector

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Pros:

  • Affordable and effective
  • Features a 10-year protection
  • Alarm sounds quickly at even the lowest levels of carbon monoxide
  • Has a permanent filter

Cons:

  • A bit bulky
  • No option to silence the alarm

Move over Carbon Monoxide detectors, the new model is here!

The Kidde Nighthawk Plug-In Carbon Monoxide Alarm Detector with Digital Display KN-COPP-3 has a 10 year life span which means it can take a straight 10 years to entirely consume its power. The alarm is activated by very minute amounts of CO. It will help protect your loved ones from contaminants and pollutants just in case the CO-levels do rise, which they can in case the burners and other machinery are left on.

The device features a digital display that shows battery power, warning levels, and the current temperature in the house. It comes with a permanent filter, a back-up silencer, and a loud alarm. Because it is a plug-in carbon monoxide detector, it can save space, especially if you are living in a really small apartment.

6. Kidde KN-COB-B-LP Nighthawk Carbon Monoxide Alarm

Our rating: 9 / 10

Kidde KN-COB-B-LP Nighthawk Carbon Monoxide Alarm

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Pros:

  • Easy to install
  • Affordable
  • Simply detects CO levels
  • Lifetime warranty

Cons:

  • Being battery operated, might not be as accurate as AC-powered detectors
  • Doesn’t have a voice alarm

In our list of top 10 best carbon monoxide detectors, we have the Kidde KN-COB-B-LP Nighthawk, which is an affordable and easy to install carbon monoxide detector. Unlike others, this one is battery operated and doesn’t require you to plug into a power outlet.

The fact that this gas detector is battery operated means that you’ll need to get lithium batteries to power it. These batteries can quickly wear out, but they’re cheap enough to afford.

The detector has a 5-year limited warranty that covers any defects in manufacture. It has been certified safe by Underwriters’ Laboratories, which means it’s a well-made product.

7. First Alert BRK PRC700 Battery-Operated Smoke and Carbon Monoxide Alarm

Our rating: 8 / 10

First Alert BRK PRC700 Battery-Operated Smoke and Carbon Monoxide Alarm

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Pros:

  • Safe for homes with pets because it’s battery-operated
  • Has an alarm that alerts you in case of a fire with a loud beep
  • Includes a 7-year limited replacement warranty
  • The metal faceplate is white, which increases visibility
  • Can be replaced separately if it’s damaged
  • Includes an 85decibel alarm that’s extremely loud
  • Has a battery backup to keep the alarm working during power outages
  • Has a countdown timer that helps alert you during being away from home

Cons:

  • Cannot be mounted on a wall
  • Must be triggered manually
  • Must be tested every month to ensure proper functionality
  • Doesn’t detect smoldering fires well

In this review, we’ll take a look at the First Alert BRK PRC700 smoke detector, which is a battery-operated smoke detector with a digital display and a 7-year limited warranty.

8. First Alert Frust Free Dual Power Carbon Monoxide Plug-in Alarm

Our rating: 6 / 10

First Alert Frust Free Dual Power Carbon Monoxide Plug-in Alarm

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Pros:

  • Digital display shows the current CO level, temperature, and battery life
  • Five-year limited warranty
  • UL listed
  • Improves indoor air quality
  • Easily installs
  • Easy to use
  • Very good price

Cons:

  • Low battery life – requires users to keep an eye on the display
  • Might detect changes in AC
  • Relatively low sensitivity
  • LED display is hard to read in strong light

For those who want a high-quality yet affordable solution, the First Alert Carbon Monoxide Detector is a great choice. This carbon monoxide detector emphasizes ease of use, portability, and affordability, which make it a fantastic option for families.

For the affordable price, this carbon monoxide detector features a digital display. You can monitor the indoor levels of CO, temperature, and battery life with just a glance at the display. It’s also combines CO detection with a thermometer using a sensor, which allows you to ensure that your home never becomes a hazard to your health.

9. Google S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide Detector

Our rating: 6 / 10

Google S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide Detector

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Pros:

  • Automatic 2-hour shut off
  • Can be configured to warn you when your furnace is malfunctioning
  • Double alarm for both smoke and carbon monoxide
  • Long three-year warranty
  • Battery operated – no need to hard-wire the device
  • Sensors are well-isolated
  • Large, white design stands out in the home
  • Works well with other Nest products
  • Transparent filter that makes it easy to tell when it needs to be replaced
  • Wi-Fi compatible

Cons:

  • Perhaps a little too expensive for many home owners
  • Small sensor gives off false alarms occasionally
  • Sensors may lose connection with the device occasionally
  • Manual is hard to understand at times, which could result in improper setup
  • Smoke particles may block sensors from detecting carbon monoxide

10. Combination Carbon Monoxide Detector and Smoke Detector

Our rating: 4 / 10

Combination Carbon Monoxide Detector and Smoke Detector

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Pros:

  • Affordable price
  • Three alarm settings
  • Easy to install
  • Slim design to fit anywhere
  • Battery backup included
  • LCD digital display
  • Smart hush feature

And Battery Backup, Smart Hush Feature, 3 Speeds Alert, Up to 90-Decibel Piercing Alarm, Battery Operated, Black.

Frequently Asked Questions (FAQ)

What are the best carbon monoxide detectors?

To quickly narrow down your options, look for detectors that are UL-2034 or UL-2075 listed. Detectors with these listings must be tested to an industry-high level for accuracy. While other detectors may be listed by Underwriters Laboratories, tests may not meet the high standards that manufacturers of true UL listed products must adhere to.

To test to US standard UL-2034, a CO monitor must measure ambient carbon monoxide levels with a minimum of 95% accuracy. Upon failure, it must be discarded and the manufacturer may not sell in North America.

What is the best location for carbon monoxide detectors?

While most carbon monoxide alarms come with several mounting kits, I wouldn't mount my CO detector anywhere. It should be plugged into an outlet where I can easily check the CO level, and it should be kept away from high traffic areas where it can get bumped. I also suggest keeping it in a central location.

Carbon monoxide detectors should be checked annually to ensure they're functioning and that batteries are changed. If your home uses gas appliances, then don't forget to check the levels regularly.

Do you put carbon monoxide detectors high or low?

A carbon monoxide detector should be placed in the middle of the house. Experts recommend placing it in the master bedroom because if there is a carbon monoxide leak while you are sleeping. It will give you the most time to escape or call for assistance before you are overcome by the poisonous gas.

It is also recommended to place carbon monoxide detectors in the lowest level of the basement or the garage. Because there is a high probability that carbon monoxide can leak from gas-powered tools including: furnaces, water heaters, stoves, cars, and dryers.

How many carbon monoxide detectors do I need?

This all depends on how big your home is. The number of detectors you’ll need is usually 1 per every 2,500 square feet of living space. As an added safety precaution, you can get 1 per every floor in your household. Alternatively, if you live in a large home like a 4,000 square foot home, then you’ll need 4 detectors. But, since most people don’t have the budget for that, the industry recommendation is 1 per every 2,500 square feet.

Conclusion

There are many different types of carbon monoxide detectors on the market, so it can be hard to figure out which one you should choose. While reading our detailed buying guide will give you the information you need to make an informed choice, we have also summarized the key points here with our recommendation for the best carbon monoxide detector of 2019.

Our Recommendation

NameCategoryProduct
First Alert CO605 Plug-In Battery Backup CO AlarmBest OverallFirst Alert CO605 Plug-In Battery Backup CO Alarm
Kidde Carbon Monoxide Alarm DetectorBudget PickKidde Carbon Monoxide Alarm Detector
Google S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide DetectorUpgrade PickGoogle S3000BWES Nest Protect Alarm-Smoke Carbon Monoxide Detector