Best combination smoke and carbon monoxide detector

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. 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

Best Visual Alerts: First Alert Combination Smoke and Carbon Monoxide Detector

This alarm offers two-in-one protection against smoke and carbon monoxide. In addition to its test and silence button, this device has two indicator lights—one for smoke and one for carbon monoxide. When one is detected, its designated light flashes to alert you of the problem. An alarm accompanies the flash unless you silence it with the button.

Key Features

  • Smoke and carbon monoxide detection
  • Visual and auditory alerts
  • Battery-powered design
  • Seven-year warranty

What Customers Are Saying

Customers 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

This battery-operated device alerts you of smoke and carbon monoxide. The device is UL-certified and features a test/hush button and a 10-year limited warranty. It also comes in larger packs of two, four, and six, allowing you to replace all of the detectors in your home at once.

Key Features

  • Smoke and carbon monoxide detection
  • Auditory alerts
  • Battery-powered design
  • 10-year warranty

What Customers Are Saying

Customers praised this device’s safety features, noise level, and ease of installation. Those who didn’t enjoy their purchase said that the product beeped randomly when there weren’t any contaminants in the air.


Best Plug-In Detector: Kidde Nighthawk Carbon Monoxide Detector

The Kidde Nighthawk Carbon Monoxide Detector can be plugged into any outlet in your home and moved around as you wish. This UL-certified device has a digital display to show you the carbon monoxide level in your room as well as a battery backup to ensure that it continues to function in the event of a power outage.

Key Features

  • Carbon monoxide detection
  • Visual and auditory alerts
  • Cord-operated design with a battery backup
  • 10-year warranty

What Customers Are Saying

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

This device protects your home from both smoke and carbon monoxide. It features a screen that shows you your carbon monoxide level in parts per million, an LED light that flashes red when a dangerous level is detected, and an alarm that starts when a contaminant is found in the air. All of these features are powered by a 10-year battery.

Key Features

  • Smoke and carbon monoxide detection
  • Visual and auditory alerts
  • Battery-powered design
  • Five-year warranty

What Customers Are Saying

Most reviewers 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

This device has a sleek, modern design and connects to your smartphone. The manufacturer’s app offers an array of features, such as a reminder when the battery is low and an alert when the carbon monoxide level is high. The body of the device also has a built-in nightlight that activates when you walk under it.

Key Features

  • Smoke and carbon monoxide detection
  • Visual and auditory alerts
  • Battery-powered design
  • Smart home integration
  • Two-year warranty

What Customers Are Saying

Customers said that they loved the Amazon Alexa integration and motion detection of this device. 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 will vary from model to model.

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 batteries. However, the batteries only last about a year before they need to be replaced. The device will usually chirp to tell you when the batteries are running low. 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 models don’t work during power outages unless they have a battery backup.

Function

Most smoke detectors 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 alarm on your detector should be loud enough to wake you up and to be heard from every part of the home. 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.

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.

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 levels of carbon monoxide:

  • 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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Are combination smoke and carbon monoxide detectors effective?

Types of Smoke and Carbon Monoxide Detectors Few combination detectors are effective at detecting carbon monoxide, smoldering fires, and flaming fires, which is why we recommend that consumers use a combination of detectors in their homes for complete protection.

What is the top rated smoke and carbon monoxide detector?

Affordable and easy to install, our top pick is the First Alert SCO7CN Combination Smoke and Carbon Monoxide Alarm. It detects both smoke and carbon monoxide, alerting you using an audio voice alert and visual alarm.

Is there a dual smoke detector and carbon monoxide detector?

X-Sense 2-in-1 Smoke and Carbon Monoxide Detector Alarm (Not Hardwired), 10-Year Battery-Operated Dual Sensor Fire & CO Alarm, Compliant with UL 217 & UL 2034 Standards, SC06. Amazon's Choice highlights highly rated, well-priced products available to ship immediately.

Is First Alert or Kidde better?

First Alert has better features than the Kidde because of the alarm system with a verbal warning of the threat.