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The Kidde 4MCO mains-powered carbon monoxide (CO) alarm is designed to last for seven years before it will need to be replaced. It comes with a rechargeable backup battery so that it will sound even during a power cut. A test button allows you to check it’s working and the alarm chirps to let you know when it reaches the end of its life. It can be connected to other Kidde alarms so that if one detects danger, they will all sound. We tested the Kidde 4MCO - the 4MDCO is identical other than it has a digital display. We tested the Kidde 4MCO back in 2019 to find out how well it detected a variety of concentrations of carbon monoxide. Read on for our verdict on this mains-powered carbon monoxide alarm and to find out whether this is the right alarm for you.
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- Aug 2024Last checked by Which?
- Dec 2019First reviewed by Which?
- Jan 2019Released
