We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies. You can understand more and change your cookies preferences here.

Kidde 4MCO review

£50.00 Typical price

Test resultShow Context

Expert review

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.

What's included:
  • Pros and cons
Sign up to unlock expert reviews
Full Access first month £2.99, then £9.99 per month, cancel at any time

Last checked by Which?

January 2022

First reviewed by Which?

December 2019

Released

January 2019

Test results

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

Find out how we test carbon monoxide detectors>
Sign up to unlock test results
Full Access first month £2.99, then £9.99 per month, cancel at any time

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Best Buys and Don't Buys
We have tested 24 carbon monoxide detectors and found that there are 10 Don't Buys and 14 Best Buys.
Sign up to unlock Best Buys and Don't Buys
Full Access first month £2.99, then £9.99 per month, cancel at any time

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

    CompareRemove all products