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First Alert CO Smoke Alarm

First Alert CO/Smoke Alarm Review

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The First Alert SCO5CN combination smoke and carbon monoxide alarm is a popular bundle coming in a pack of 4 battery-powered units.

They are easy to install without having to call in an electrician, adding to the cost.

The First Alert smoke/CO alarm is suitable for both the family home and for rental properties, especially if they have a fireplace or might need to operate on a generator from time to time due to mains power problems.

With CO gas being odorless, you must be alerted to a problem you might otherwise not be aware of.


Overall Score: 4.6/5
  • A combination of smoke and CO gas detector saves you from having one of each per location. Indicator lights tell you what activity the sensor has detected.
  • Bundle of 4 units makes sure you can get good coverage of your house.
  • Battery-powered so you don’t need an electrician to install them.
  • 7-year limited warranty for peace of mind
  • Meets UL safety standards.
  • Does not include voice feature to advise which alarm has activated.
  • Does not comply with State of California regulations that require a sealed unit with 10-year battery life.

A bundle of four units means that you can cover the whole house and not just the room that may present the highest risk.

This alarm comes complete with an easy to mount base plate.

The combo alarm is easy to install and easy to remove to replace batteries, which you should, of course, be doing once a year.

The First Alert alarms have lights to let you know whether it was smoke or gas that activated the alarm, allowing you to do a quick audit to find out where the problem is and decide how to deal with it.

How easy is it to use?

The First Alert alarm is easy to use and test, delivering simple to understand information provided by audible alarms and lights.

Ease of use makes it not only suitable for the family home, but also for a rental property where you are not relying on the technical expertise of your tenant to ensure that alarms are working as they should.

How accurate is it?

The combination of a photoelectric sensor for smoke and an electrochemical sensor for gas allows it to reduce the likelihood of a false alarm from cooking smoke or shower steam.

How easy is it to install?

The First Alert combination smoke/CO alarm comes with a base plate which is quick and easy to mount, and the alarm unit just slots into it.

As it is battery powered, it can be easily installed anywhere in the house, without having to call in an electrician.

The batteries come included, which is a plus. It can be very frustrating to install and appliance and not be able to set it up and test it because you do not have batteries.