Kidde AC Plug-in Carbon Monoxide and Explosive Gas Detector Alarm | Nighthawk Sensor Technology | Model # KN-COEG-3

Good CO detector, has 12v backup battery and 110 v plug in main power supply with a long (4’cord). This is a replacement for the first one I purchased 5 years ago. These units have a 5 year design life once they are plugged in. After 5 years of operation they automatically stop working and sound an alarm and message to replace the unit. I like the display, bright and legible red lettering and the alarm is loud enough for me to hear it upstairs even though it’s located in the basement. Yes, I will probably purchase again.

Year old, with a bad battery. I ordered and received the unit the same day. It was new old stock (NOS) made late 2024. Not idea. AND even worse, as soon as I plugged it in, the unit alarm started sounding with what looked like an "L6" error display. Turns out that was actually a "L" as in "Low" and "b" as in "battery". So I checked and indeed the shipped bat was low. I replaced it, after calming my family down about false alert, and the unit is now working properly. I'm ordering two more and will update this review if those two are newer and/or have good batteries.

This is something I consider a necessity. The size is not obtrusive and the design is simple. It can be plugged in a wall outlet directly or the plug can be removed from the holder to reveal a cord so it can be set on a shelf if needed. It has a battery backup. The alarm is loud so you will hear it if detection is made. It is easy to read the display. The only thing I was a little annoyed at is that it was made a year ago so we lost a whole year on the lifespan.

Always purchased previously. Discovered the expiration date was already outdated. Kept indicating carbon, had local fire-station try it and same thing happened. ±±Bought different brand from Lowes that works great, 5 yr warranty, etc. Important that you have a carbon doctor that works.

I purchased several of these and all of them worked except one. One kept beeping and needed to be replaced. I called the company and they replaced it. I like the fact that the company stands by it product.