Kidde Carbon Monoxide Detector, Plug-In with 9V Battery Backup, Digital Display, 85 dB Alarm, LED Status Light Indicators, 3rd Edition

I needed this for a rental property that we are selling. It provides both battery backup as well as plug in power. It is easy to operate, inexpensive and does the job.

I purchased the Kidde Carbon Monoxide Detector for my home to replace another unit that had expired. The Kidde Detector plug-in design with a 9-volt battery backup is very convenient & easy to use. It offers continuous protection even during power outages. The digital LED display clearly shows CO levels, which is helpful for peace of mind. Unit came ready to use, with battery already installed. We just pluged it in and it was ready to use. We feel confident that our family has chosen a great carbon monoxide detector for our home.

Bought as a replacement for detector that met its 10 year lifespan. Easy to install by just plugging it in to a wall outlet. Appreciate that it comes with a 9-volt backup battery. A potential lifesaver that functions reliably in the background.

My mom installed 2 of these in her house 7 years ago. They both failed and started going off within 2 days of each other. Might have been just a dead battery. I don't know. She called me and said they needed replaced so I got 2 of the current model and installed them for her. I like that these units have a digital readout feature that allows you to pull up not only the current CO level but also the highest level since the last reset. As someone who works around fuel burning appliances as part of my job, I know that CO levels in a structure can vary, and it is important to know not only what the reading is right now, also to know how high the reading has been previously as CO levels can change as appliances or vehicles run, doors or windows open, etc. Even a high quality handheld unit that the fire department or gas company uses to investigate CO complaints is limited because it only knows what the CO level is right at the moment of the test. Meanwhile, this inexpensive digital CO detector cannot only tell you what the level is right now, but also the highest level it has noted...which is an important data point. I also like the way these units can be plugged/mounted directly to an outlet, or you can extend the plug from the unit and mount it a few feet away (perhaps above) the plug to get it into a better sampling position. I gave this unit 4 stars which is the highest rating I would give any of the readily available home CO detectors. Why not 5? Well, they still have a limited service life (like 7 years), and it would be nice if when they fail they would have a different alarm or some very clear indication that the reason it is going off is it has failed, not because it has detected CO. In my 83 year old mother's case, she had the police out there in the middle of the night because her old detector had gone off...and that is very common. When these units fail, it shouldn't initiate a call to 911. They need to make it much more obvious to the homeowner that the unit needs replaced, but there is no reason to call emergency services.

Quality Kidde brand CO detector. I replaced my original one with this identical one after 10 years of service, when it finally beeped and showed "END" in the display, which renders it useless, which is by design. Ironically, I never had any CO issues or alerts, until about a few months before its 10th anniversary in service. My home's natural gas boiler was over 25 years old, and begin leaking CO from incomplete combustion issues. This Kidde CO detector audibly alerted me and displayed the current CO level as well as the maximum CO level that it had recorded. Very simple to use and displays basic, yet useful information. I was able to open the windows and ventilate my house to prevent the excess CO buildup from harming us, thanks to this CO detectors audible & visual alerts. Hope they're still making this model 10 years from now, when I will need another one, or if I decide to move and want to purchase a new one. It's certainly not the cheapest CO unit on the market, but it's a good value for the money. Oh, it plugs directly into any standard 110-volt power outlet and it has a 9-volt battery backup, battery included. Although they recommend you replace the 9V backup battery every few years, I never replaced mine, and it was still almost as good as the day it was installed. My Kidde CO detector is plugged into an outlet in our upstairs hallway just outside of our bedroom. Fortunately, it also fit perfectly next to (below) my plug-in doorbell, which was a huge plus! I'm planning on installing one in the basement, near the gas boiler as well. Should have done that years ago, as we would have likely received an earlier "heads-up" that there was a combustion problem with the boiler. One last note: You can remote wall-mount this unit also. Cool feature! If you look at the last picture that I posted with this review, you can see that when the rear access cover is removed to access the backup battery, there is extra cord stored on the opposite side of the battery. The connected main power source plug can be easily removed and relocated/extended, via the corded connection, in order to have the CO detector located somewhere other than directly plugged into the power source. There is also a handy little clear plastic packet included, containing two wood/mounting screws and two wall mount plastic expanding inserts. (Not shown in picture.) Just can't say enough good stuff about this unit. Very pleased with it!

Came with corroded battery but worked OK once it was replaced. Last one lasted 10 years theen they apparently become inoperable.

I have a boiler in one of the bed rooms so thought it was important to have a good alarm .put battery in plugged it in .Reading came up as "0".The next morning it did intermittent bleep I went to check it the battery was flat the plug was red hot ,fire hazard so I sent it back cost me £12.75 to send it to Spain !!!