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"The First Alert Carbon Monoxide Detector is nice and compact. You can use it as a portable unit, or you can hang it up on the wall. It is very easy to set-up, just remove from the box and turn the switch on. I recommend everyone getting a carbon monoxide alarm, because you just never know."
"I like this detector. It’s not large in size and instead of mounting on the wall, It can sit upright on a countertop or shelf. The digital thermometer is also an added bonus. When testing to see how the alert would sound, I like that it does not sound the same as a smoke detector."
"First Alert Carbon Monoxide Detector with Digital Temperature Display is perfect for our home. It gives us the detection we want and need with updated style and digital features. This product would be prefect for any sized home and I recommend that anyone get one of these products. We are very pleased with this product and highly recommend it."
The First Alert CO400 is a battery-powered carbon monoxide alarm for homes that want protection on every level and outside bedrooms, and that keep working when the power fails.
It uses an electrochemical sensor to measure carbon monoxide and sounds an 85 dB alarm when levels become dangerous.
Because it runs on batteries, it keeps monitoring during a power cut. An end of life chirp tells you when the unit needs to be replaced.
First Alert Smoke Detectors is tested to UL standards and recommends one on each level of the home and in each bedroom area. It measures about 5 by 3 by 1 inches, weighs about 0.7 pounds, and has a five year limited warranty.
The listing does not say which batteries it uses or how long they last, so check the box and note the date you install them.
Test it monthly, the alarm should sound for five to six seconds and if it does not, replace the batteries and test again, then replace the unit.
A CO alarm does not detect smoke, so you also need smoke alarms. If it sounds, move outside into fresh air and call emergency services. Keep it clear of dust and of direct heat.
Before you install the First Alert CO615 Dual-Power Plug-In Carbon Monoxide Detector you’ll want to test it to ensure that it’s working properly.
✓ Press the “test” button on the front for a few seconds, it will be followed by a round of loud beats.
✓ Wait for the screen to light up blue and run through the different icons, showing you how it would look if the device detected carbon monoxide and at what level. The screen will also show the battery life so you always know how much is left.
✓ For batteries: The monitor will beep when the batteries are low or dead, though they’re only in use when you unplug the device.
✓ Install carbon monoxide alarms on every level and in every bedroom.
✓ Test your alarms regularly.
✓ Replace alarm batteries every six months.
✓ Alarms don't last forever, remember to replace alarms at least every 10 years.
✓ Do not use generators, gas powered tools or grills inside the home.
✓ Service fuel burning appliances and chimneys annually.
✓ If your alarms sound, leave immediately for fresh air and call 911.
Choose your pack
Starter
First Alert CO606 – Plug-In Carbon Monoxide Alarm with Battery Backup
$29.99/pack
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First Alert CO615 – Plug-In Carbon Monoxide Alarm with Battery Backup & Digital Display
$39.99/PACK
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First Alert CO400 – Battery Powered Carbon Monoxide Alarm
$24.99/pack
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Choose your pack
Starter
First Alert CO606 – Plug-In Carbon Monoxide Alarm with Battery Backup
$29.99/pack
FAST SHIPPING
Order nowMost popular
First Alert CO615 – Plug-In Carbon Monoxide Alarm with Battery Backup & Digital Display
$39.99/PACK
FAST SHIPPING
Order nowMost popular
First Alert CO400 – Battery Powered Carbon Monoxide Alarm
$24.99/pack
FAST SHIPPING
Order nowOnce you have clicked the First Alert “Buy Now” button that is right below this text, you will be taken to the secure page. Then just enter your information, and select the desired package to complete your order, and your First Alert will then be processed and shipped to you.
For best Wi-Fi connection results, follow these steps:
1. Scan QR code shown in STEP 1 on the front of the Quick Start Guide. Install the Kidde app.
2. Open the Kidde app. Create and login to your account. Tap “Add a device.” Select “SMART Smoke + Carbon Monoxide Alarm.” Follow in-app steps.
3. Scan your unique QR code, shown in STEP 3 of the Quick Start Guide, or on back of your alarm. Setup and connect alarm to the app. This will include instructions about wiring and installation (see sections 9, 10, and 11 of the user guide).
This indicates the device is in wireless setup mode and ready for configuration with the Kidde app.
In low light ambient conditions, the green LED ring fades to off, and then blinks approximately every 60 seconds. This unit samples the ambient light conditions of the alarm’s location and, if possible, determines a Night / Day cycle. A valid Night / Day cycle will delay unit chirps during the night until the next Day cycle begins.
Go to your device's app store, search "Kidde" and the app should allow you to click "install" or "download" to install the app on your device.