First Alert CO710 review

What it is and who it suits

First Alert describes the CO710 as an alarm that needs no installation: you place it on a tabletop or shelf. It uses an electrochemical sensor, sounds an 85-decibel alarm when elevated carbon monoxide is detected, and has a single button to silence and test it. First Alert's product page now returns a not-found error, so we read an Internet Archive copy from June 2025, which lists the model as 1039753, with a 10-year limited warranty, a weight of 0.5 pounds and a size of about 4.75 by 2.63 inches.

It suits a household that wants an alarm that does not depend on an outlet or on battery swaps, including a travel alarm, since First Alert pitches it for a vacation rental or hotel room. First Alert says it is intended to sit on a flat surface unlike alarms designed to mount on the wall.

The battery and the display

The battery is a built-in 10-year sealed lithium battery, which First Alert says removes battery changes and low-battery chirps for the life of the alarm. The battery is not replaceable, and an end-of-life warning tells you when to replace the whole alarm. Because it has no outlet plug, it keeps working during a power outage.

The backlit LED display can show room temperature, current carbon monoxide concentration and the recent peak level in parts per million. First Alert says the stored peak reading can give useful information to emergency or hospital staff after an incident.

Where to put it

CDC says to install battery-operated or battery back-up CO detectors near every sleeping area in your home. CPSC says CO alarms should be placed on every level of the home and outside sleeping areas, that they should be battery-operated or have battery backup in case of a power outage, and to test them every month. Ready.gov says to install detectors with battery backup in central locations on every level of your home.

First Alert says placing alarms on every floor and in each sleeping room is an important way to protect your family. One CO710 covers one spot, so plan on several, and place them as the instructions with the alarm direct.

Why an outage raises the stakes

CDC says carbon monoxide is an odorless, colorless gas that kills without warning. Ready.gov says never to use a gas stovetop or oven to heat your home, and it says generators and fuel should always be used outdoors and at least 20 feet away from windows, doors and attached garages. Our carbon monoxide poisoning guide lists the warning signs and our generator safety guide covers placement.

An alarm is a backup to those rules, not a replacement. Our carbon monoxide alarm comparison sets this model beside combination smoke and CO alarms.

Who should skip it

Skip it if you want one device for smoke and carbon monoxide, since this detects carbon monoxide only. First Alert's page does not describe this model as wall-mountable, so skip it if you want a wall-mounted or interconnected system. Replace it when it signals end of life.

Does the First Alert CO710 work in a power outage?

Yes. First Alert describes a built-in 10-year sealed lithium battery, with no plug-in or battery changes needed. Its end-of-life warning tells you when to replace the alarm.

Can I replace the battery?

No. First Alert lists the battery as not replaceable. The alarm has an end-of-life warning, and a 10-year limited warranty.

What does the display show?

First Alert says the backlit display can show room temperature, current carbon monoxide concentration and recent peak levels in parts per million.

How many alarms do I need?

CDC says to put battery-operated or battery back-up CO detectors near every sleeping area. CPSC says to place them on every level of the home and outside sleeping areas, and to test them every month.