Kidde Carbon Monoxide Detector, AA Battery Powered CO Alarm with LEDs, Test-Reset Button, Low Battery Indicator, Portable

I purchased the Kidde Carbon Monoxide Alarm ten years ago, and today, it reminded me of its reliability with a loud, audible chirp and a display reading "END," indicating that it has reached the end of its useful life. Over the years, this unit has proven to be incredibly accurate and dependable, providing me with peace of mind regarding my family's safety. It is long overdue that I write this review.One of the standout features of this alarm is the ease of replacing the batteries when needed. It’s a simple process that ensures the unit remains functional without any hassle. I appreciate how straightforward it is to maintain, allowing me to focus on what truly matters—keeping my home safe.Given my positive experience, I will definitely be purchasing another Kidde Carbon Monoxide Alarm to continue enjoying worry-free living for another ten years. Highly recommend this product for anyone looking for a reliable and user-friendly carbon monoxide alarm!

Attractive; Easy to Activate; Detects and Alarms Appropriately.I always read the 1 star reviews before buying a product. Some disturbing comments were: "batteries are impossible to insert" -- I had no trouble inserting the batteries (fit firmly but install with gentle pressure); "Tested with CO and got NO Audible Alarm" -- this was a big red flag, so I tested my unit upon activation. At 500+ ppm CO got good LED visible readout, but NO audible alarm. Was ready to repackage and return, but re-read the product information sheet: "This alarm measures the exposure to carbon monoxide over time; it is designed to sound at 85 decibels at 10 feet when it detects 70 ppm (parts per million) of CO for 60 to 240 minutes, 150 ppm for 10 to 50 minutes, or 400 ppm for 4 to 15 minutes." I retested, exposing unit to 400-650 ppm CO and got an audible alarm at around 6 minutes. Removal from source, display returned to zero and audible alarm ceased. Much more assured that the unit works properly. And Audible Alarm times are well within guidelines for exposure to CO and symptom development (see photo). Also really like that I can replace batteries. Previous units with sealed batteries didn't last anywhere near the 10 year "useable life" advertised.

Great monitor at a fair price. Especially like the ability to see a constant ppm level and an easy test function. I use mine in the garage but it could be mounted anywhere. The alarm is plenty loud so it should have no issues alerting even over the loud engine noises.

Placed in key spots up & downstairs. I use separate smoke alarms. One downstairs, one in hall upstairs and one each bedroom. I know over-kill. My son is a fireman! Batteries went dead in Co2 detector's in two years. Wrote when the batteries were replaced on the back cover. A hint. Used better batteries lasted 5 years then gave up the ghost. Over-all, good product but not a ten year life. Meets all local requirements. Better safe than sorry.

Arrived on time and in good condition. Add batteries and mount to wall. Easy peasy. I bought 2 and installed 1 on main level and 1 in lower level about a month ago, and the readout on both is 0, so that is great. Would buy from them again.

With emergency products like CO detectors, it's hard to know if they really work unless you're actually being exposed to dangerous amounts of CO. And if a CO detector doesn't work, you wouldn't know; instead, you'd just be poisoned while thinking that nothing was wrong. The only way to really find out if it works is to put it in an airtight container and generate CO.Because I like to play with dangerous chemicals at home, I decided to try this out. Adding formic acid to concentrated sulfuric acid causes the formic acid (HCOOH) to break down into CO and H2O. I got both of these chemicals for less than $10/liter apiece, plus shipping. I put some sulfuric acid into a graduated cylinder and placed it in a 1-gallon airtight plastic container. I then added small amounts of diluted formic acid and rapidly closed the container.Sure enough, it worked! It registered CO concentrations that were well within the ballpark of what I'd expect to get with the amount of formic acid I added (using the ideal gas law to figure out what the maximum CO level would be). In high concentration tests, I found that the alarm goes off within 3 minutes of hitting 500 ppm (which is dangerous but would take several hours to kill, giving plenty of time to get to fresh air). In another test, it went off after about 20 minutes of CO levels around 190 ppm, which is dangerous but not lethal. Its peak reading is in the 910-920 ppm range; it doesn't display levels higher than that. Needless to say, it goes off within a minute or two of such high CO levels and anybody who sees 900+ ppm on the display should leave their house and seek medical help immediately.It worked well in low concentration tests too. Due to some strange US regulation, it displays "0" for any reading below 30 ppm. If you press the "peak level" button, though, it will tell you what its peak reading was even if it was below 30 ppm. This works down to the 10-15 ppm range, below which you don't really have to worry about CO at all. Prolonged exposure around 50 ppm leads to an alarm after a couple of hours.Another, simpler test (which anyone with a CO detector should do to make sure it's working) is to light a candle in an enclosed container with the CO detector, then close the container. The candle will burn through the available oxygen and a fair amount of incomplete combustion (releasing CO instead of CO2) will occur as it runs out of O2. I tried this and got 96 ppm with a small candle in my gallon container; a larger candle would probably release more. I then tried it by lighting a crumpled piece of newspaper in the container and got >910 ppm, which is reasonable because paper and wood experience pyrolysis, which releases lots of CO. Combustion of small amounts of acetone (a fairly clean fuel relative to paper) resulted in 300-550 ppm depending on how hot the fire got before I put the lid on; the lower reading relative to paper helps confirm that it's reading accurately.In conclusion - this $20 detector works very well when tested with real CO. It's accurate, the alarm goes off at dangerous CO levels, it only goes off if CO levels are dangerous, and it might just save your life.

I originally purchased 2 of these units on 2/18/2015. Yesterday, 3/10/2025, one of the units started chirping every 30 seconds. The display read "END", meaning that the detector has expired, and will no longer work. The instructions explain that these detectors have a 10 year life span. No complaints here! I am about to order 2 exact replacements, as I expect the second unit to expire soon. I mount one in the basement and one in the hallway outside the master bedroom.I highly recommend this product.