First Alert CO605 plug-in Carbon Monoxide detector with battery backup white review


Why do you need First Alert CO605 plug-in Carbon Monoxide detector with battery backup? You need a trustworthy, long-lasting alarm to keep your family and house safe and secure, and this one meets those requirements. The most precise technology now used is an electrochemical carbon monoxide sensor, which is what the First Alert CO605 plug-in carbon monoxide alarm with battery backup employs. Without any additional mounting, the alarm is simply plugged into any regular socket. A battery backup makes sure the alarm functions even when there is no power, and a mute button turns off any unnecessary alarms. We discuss more in First Alert CO605 plug-in Carbon Monoxide detector with battery backup white review.

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Pros & Cons


  • Easy to Use
  • Electrochemical CO Sensor
  • Dual Power option


  • No wireless connectivity

Best Seller in US

Best Seller in UK

First Alert CO605 plug-in Carbon Monoxide detector Specs

  • White COLOR
  • Power Source Corded
  • Electric Style Plug in Alarm with Battery Backup
  • Dimensions of the item are 3.4 x 1.38 x 5 inches.
  • Weight of Item 0.26 Pounds
  • Alarm Combustible Oxide
  • 85 degrees Fahrenheit for the lower temperature rating and 105 degrees Fahrenheit for the upper temperature rating
  • Battery Backup Yes
  • Backup Battery Size 9V
  • Battery Replaceable Yes
  • Wireless Interconnectivity No
  • Sensor Type Electrochemical
  • Power Supply Plugin


It is good quality, good price. It is available in the market at $29 in most of the retail stores.

Why do you need Carbon monoxide alarm detector?

When consumed in greater quantities, carbon monoxide can kill you instantly or severely damage your health over time. Take no chances. The gas is not visible or odorous.

First Alert CO605 plug-in Carbon Monoxide detector with battery backup white review

Build & design

First Alert CO605 plug-in Carbon Monoxide detector has a length of 3.4 inches, width of 1.38 inches and this item height is 5 inches. It is round shaped and match with your home decor.

CO sensor

Contains a cutting-edge electrochemical carbon monoxide sensor that reliably measures carbon monoxide levels regardless of the location of the detector in the space.


When carbon monoxide concentrations are hazardous, an alarm with a sound level of 85 decibels sounds. The alarm’s sound is really loud, so if it does go off, it will definitely awaken you if you are asleep.

Battery life

The low battery indication is muted and quieted for up to 8 hours. This one lasts for seven years and notifies you when it needs to be replaced.


So simple to use. You may use it by simply plugging it into any socket. You’ll appreciate the plug-in design’s simplicity and backup battery’s inclusion. There is no complex hard wiring. Putting this in the visitor room. You may test the alarm by pushing a button, and it is loud enough to wake those who are sleeping (they advise you to do this once a week).

First Alert CO605 plug-in Carbon Monoxide detector with battery backup white – consumer reviews

No Mono Here.

This is the 2nd set of 2 Carbon Monoxide Alarms I have purchased from First Alert and I expect this pair to be just as reliable as the previous set. I had the previous set for 10 years so I thought it was time to replace them with newer technology. The neat thing about this pair is the ease of installation. you just plug them in and you’re done. be sure to test the units once a month to be sure they are working. there’s no other way to tell unless you actually have a carbon monoxide leak and thank God they’re working.

By John Kalabokes at firstalert

First Alert CO605 plug-in Carbon Monoxide detector alternative

Kidde Battery-Operated Combination Smoke and Carbon Monoxide Alarm

A dual-purpose carbon monoxide detector can effectively safeguard your family and house from dangerous gas leaks and warn you of a potential fire hazard. Similar in size to a typical smoke detector, the Kidde Smoke & Carbon Monoxide Detector also has an electrochemical sensor to detect carbon monoxide.

This kind loudly declares “Warning carbon monoxide” or “Fire” if an alarm is set off. The voice announcement also indicates whether or not a low-battery alert has been triggered.

It’s also important to note that the Kidde Smoke & Carbon Monoxide Detector employs an ionization sensor, which is more likely to detect a fire that is burning quickly than one that is utilizing a photoelectric sensor.

Two AA batteries are required for this smoke and carbon monoxide detector combo. It is compliant even in states where smoke detectors must have a 10-year lifespan due to its 10-year use rating.

This device’s Smart Hush feature silences the alarm for 8 minutes if cooking or other activities cause a false fire alarm, as happened with our at-home tester, allowing you time to clean smoke from your cooking accident or your snuffed candle.

FAQs on First Alert CO605 plug-in Carbon Monoxide detector

Why First Alert plug-in carbon monoxide detector red light is blinking?

A red or green light that blinks every few minutes on some alarms serves as a visual cue that the alarm is getting electricity and is operational.

When does First Alert carbon monoxide alarm END error appear?

The “END” symbol on the display of your digital carbon monoxide alarm indicates that it has reached the end of its useful life and has to be replaced. Additionally, the alarm will chirp five times per minute to alert you when it needs to be replaced.

When does First Alert carbon monoxide alarm beep?

There are three basic causes for its beeping. You should leave the area and dial 9-1-1 if you hear four beeps followed by a pause, which indicates an emergency situation and the presence of carbon monoxide in the vicinity. Low Battery is indicated by 1 Beep Every Minute. The batteries in your carbon monoxide detector need to be changed. The device’s End of Life is indicated by 5 beeps per minute. Your carbon monoxide alarm has to be replaced if it makes this kind of chirp.

When is Carbon monoxide detector went off then stopped?

One of the following factors could be the cause of your carbon monoxide alarm:
It correctly performs its function by identifying CO pollution in the atmosphere. Other items in the house set off the false alarm. The batteries need to be replaced or the detector has to be repaired.

Editor’s recommendations

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