First Alert CO400 Battery Powered Carbon Monoxide Alarm | CO400

I bought five of these and installed them in minutes. I’d recommend this to anyone.

I recently purchased this First Alert CO400 detector to add another layer of safety to my home, and I’m very satisfied with the experience. What I appreciate most is the straightforward, battery-operated design. It was incredibly easy to set up—no hardwiring or complex installation required, which makes it perfect for placing exactly where you need it without worrying about electrical outlets. The unit feels sturdy and well-built, and the alarm is loud and impossible to miss. It provides great peace of mind, especially given how unobtrusive and reliable it has been since I installed it. For anyone looking for a no-fuss, effective way to monitor carbon monoxide levels in their living space, this is a solid, must-have product.

I purchased this alarm to install in the upstairs hallway between bedrooms. It was very easy to install and works perfectly and provides the added security I required. I was surprised and happy at how quickly the parcel arrived!

Installed as soon as they arrived to replace older models that the batteries had expired in (7 year batteries and no maintenance or replacement option). These do have batteries that have to be or can be replaced. The 2nd night after installation, the detector I had mounted in my bedroom (installed all 6 throughout my house) went off around 2:00 AM and awakened me. I immediately shut my gas furnace down and called a HVAC company. They found a crack in my heat exchanger as well as issue with the flue or exhaust pipe that was allowing CO to enter my home. Had I not replaced my CO detectors when I did, I wouldn't be writing this review now. Well worth my investment!! Easy installation and had all 6 up and operating in less than 30 minutes as well as reasonably priced. Purchased this pack of 6 for less that the other 2 I had bought 7 years ago.

Quickly mounted to the wall and put batteries in. Tested. Made beep noises that split eardrums. Due to the battery nature of it it can mount anywhere close to the ground to detect CO quickly. I wont truly know if it works, and I hope I never need to, but appears solid.