Nest Protect Smoke + CO Alarm review
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The Nest Protect Smoke + CO Alarm can send alerts about dangerous levels of carbon monoxide or smoke direct to your smartphone, which is a handy touch if you’re out of the house at the time. This more advanced two-in-one functionality, along with its 10-year lifespan, pushes the price up far above the price of a standard CO alarm. This review is of how well the Nest detects CO, but it's also a smoke alarm and since testing it, the law on smoke alarms has changed in Scotland. This means that as the Nest doesn't come with a heat detection function, it won't be suitable for Scottish homes from 2022. We put the Nest Protect Smoke + CO Alarm through a series of stringent carbon monoxide safety detection tests to find out how well it detects the deadly gas. Read on for the results of our tests.
What's included:- Pros and cons
Last checked by Which?
January 2022
First reviewed by Which?
August 2016
Released
January 2016

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