KiddeHardwired Smoke & Carbon Monoxide Detector, AA Battery Backup, Voice Alerts, Interconnectable, LED Warning Light Indicators, 1 Pack

I had to replace the “Primary Detector” from a Kidde 4 alarm set that was installed 11 + years ago. When doing the Kidde model number search on Amazon, this was the top of the search. I am glad it was since the secondary or linked bedroom alarms also showed up in the search. So I made a lucky decision on the right model, as this one was ~3 times the cost of the others. It was easy to install as all I had to do was replace the connection plug as it was a slightly different plug style but the prongs were exactly the same line up and this unit linked up perfectly to the bedroom alarms. I did pick up a First Alert 2 pack from Costco, but the prong set up was different, so I did not want to install those as I was not sure they would connect to the others right. Kidde replacement works great.

I love my local hardware store, but the same unit was substantially more expensive for this same unit so I just bought it on Amazon, sorry HD. I have a wired system in my home that I also connected to SmartThings and Alexa using. Anyhow, this unit adds a clear voice and the co sensor to my existing system. Normal install and it works fine.

I had the Kidde CO/smoke combo unit up for over 10 years and it finally gave it up when the end of life signal went off (of course at 2:00 AM and cathedral ceilings) I ordered the new model right away from Amazon and I received it that morning! (Prime) I did replace the mounting plate and harness, since it was different, with no issues. I didn't even have to cut the power (just make the hot (black) connection last :) Works great, no false alarms. BTW I never had to replace the batteries in the original Kidde unit after 10+ years, they were the original AA Mercury/Cadmium cells the unit came with! Impressed...PA Colorado

Took 10 days to get, which is irritating because the old unit only has one 7 day silence period when expired. Bought this unit because Kidde said it was the replacement for the KN-COSM. It is not a drop in replacement. Although the mount is the same and interchangeable, the wiring connector is different. The instructions are complete and good, except they do not cover replacing the older unit. They say to hire a licensed electrician to connect the pig tail to the system. They also say to cut the circuit breaker which is suppose to be on a dedicated circuit. Turns out mine is not on a dedicated circuit, and not labeled, so I was unable to determine which circuit it was on. So I ended up changing the pig tail out with it hot. Not too dangerous if you know what you are doing, do only do one wire at a time and are not grounded. In the end I got it replaced and the new one is working.

Easy to install.

I had two of the older designed Kidde Hardwired Smoke & Carbon Monoxide Detectors. They were wired together with five Kidde hardwired Smoke Detectors. The detectors were 7 - 8 years old. On a regular basis, I would get false alarms--usually in the middle of the night for no reason. With regular back-up battery changes, I was getting chirping and false alarms. Being frustrated, I replaced all the alarms with the same Kidde brand. The smoke detectors were a retro fit--plug and play. The new designed Kidde Hardwired Smoke & Carbon Monoxide Detectors fit on the same mount, but required changing the electrical harness. This wasn't a big deal, turn off the power and match the three wire colors with a twist connector. Delighted to report, that all the alarms are working perfectly. No false alarms and no chirping. Very pleased with the purchase, but am hoping that these last longer than the last set. Time will tell. Saved a ton of money not having to hire an electrician.

I got this to replace our in-home smoke detectors that had just gotten old. They are easy to install and seemingly work great. Luckily, we haven’t had to try them out in an actual emergency, but I am confident in this brand.

This was easy to replace my old one which got corroded. Mine was old so had to replace the wiring harness. This only took a couple of minutes to swap out.