Kidde KN-COSM-BA Battery-Operated Combination Carbon Monoxide and Smoke Alarm with Talking Alarm , WHITE

I bought this Kidde KN-COSM-B Battery-Operated Combination Carbon Monoxide and Smoke Alarm with Talking Alarm last July, since one of my old carbon monoxide alarms started 'chirping' (due to end-of-life). So far the Kidde alarm seems to work really well. Of course, as with any safety devices, you never know it actually works until something BAD happens. So it is more for "peace of mind" than anything else. The 'Talking Alarm' feature is a great help because it makes the device so much easier to use than any of my previous detectors. For example, once I inserted three AA batteries, the device goes through the test procedure, by saying "Testing" "Fire, Fire" "Warning, Carbon Monoxide" As the battery voltage gets too low, the device will actually say "Low battery". That means there's no need to dig up the product manual and struggle to read the tiny prints, in order to understand the meaning between 'long beep' or 'short beeps', and so on. If you don't have all three AA batteries installed, a safety latch prevents the device to be mounted to the base plate. This is a good safty feature, since it prevents people from simply hanging an alarm on the ceiling without batteries inside. The battery consumption is very low. I measured 0.10mA in standby. An alkaline AA battery has a rated capacity of around 3000mAh in light load. So a set of 3 AA alkaline cells should last for 30,000 hours, or over 3 years. By the way, all carbon monoxide detectors have a built-in termination date of around 7 years (something to do with the half life of the radioactive isotope in the detector). So remember to replace them promptly. [Side Note] Some people may want to use low-self-discharge rechargeable batteries such as Sanyo eneloop in smoke detectors. But that does not make economical sense in this case, since you only replace/recharge the batteries once every 2-3 years. Also in general it is not safe to use rechargeable NiMH batteries in safety devices. This is because the low battery detection circuit is designed for alkaline batteries. The voltage profile of alkaline cell starts from 1.6V and drops linearly as the battery is used up. The low-battery warning is designed to give at least one week of warning before the voltage drops too low. In the case of NiMH cell, its voltage profile stays flat at around 1.25V for most of its discharge period. But it drops rapidly as the battery is exhausted. So the warning period could be shortened to a few days of just hours. For the same reasons, using Energizer AA Lithium Batteries is also not a good idea.

This purchase was an exact replacement for the previous one in my bedroom . . . which automatically deactivated itself at the end of its 7 year lifespan (a built-in feature of this alarm). This alarm provides a voice system as well as the beeping alarm to alert the owner of either "fire" or "carbon monoxide". Both features have sounded in my home in the past, resulting from: using a cooking stove as a heat source, and on another occasion, closing the damper on the fireplace too soon after I thought the fire was out. So --- this thing works. Nice silence feature allows you to silence nuisance alarms (such as smoky cooking events) for 8 minutes simply by pressing the test button. Takes 3 AA batteries (which I prefer to the 9 volt battery that most detectors require). And, I love the mounting system: The mounting plate screws to the ceiling or wall, then the detector unit snaps into the base plate with an easy push and a turn. This allows the owner to easily take it down for battery replacement (instead of standing on a chair trying to snap in a battery). It also allows the unit to be taken down and relocated elsewhere (like outside or the garage), when there is a persistant nuisance alarm situation (like smoky cooking). This is my second one and I've found them to be trustworthy and easy to operate and maintain. 5 star device.

It was time to replace the battery on our NIGHTHAWK smoke detector and I realized that it had been manufactured in 1999! Checked the plug in NIGHTHAWK carbon monoxide detector and found that it also was manufactured in 1999. They both were working well when tested, but we've fortunately never had a fire or carbon monoxide experience, so the alarm warning was never utilized for evacuation purposes. We changed the batteries, but figured it was time to replace both units. After much research, the Kidde KN-COSM-B Battery-Operated Combination Carbon Monoxide and Smoke Alarm with Talking Alarm (also NIGHTHAWK product) was the clear winner. It was a little difficult to remove from the plastic shell packaging but was a breeze to install. The alarm will not snap into its holder without batteries in place, so on the day I was ready to install, I put in the (3 enclosed) AA batteries (must insert them in the order specified in the battery compartment) then twisted the alarm onto its holder and tested the alarm. All it's warnings functioned properly, so the old alarm was removed from the ceiling and the new base was installed onto the same ceiling location. The alarm was twisted into place and the it was tested a second time. My unit was manufactured five months ago but from what I understand, the 7 year self-destruction warning sounds 7 years from the date the batteries were installed. I personally would not purchase this in an opened package for that reason -- could be that someone inserted the batteries a year ago and returned the item. The included manual specifies that certain AA batteries be used and I don't know what occurs if one uses another brand. When I have time, I'll contact the company to check that out. I hope to only hear the warning "voice" from this alarm every time I press the test button but am comfortable with the security I feel knowing this alarm is functional. Its warranty expires in 5 years.

I've installed installed two of these Kidde brand combination smoke and carbon monoxide detectors in my elder parents home. I have one in my own home as well and have found them all to be reliable and trouble free. What attracted me to this model were its many features: First, it has a low profile, attractive and unobtrusive design. Second and perhaps most important, it has a voice speaking function that, in addition to the 85db alert horn, will speak out clear warnings: "FIRE, FIRE" or "DANGER: CARBON MONOXIDE". I think that this feature is a terrific addition toward modern life-safety technology. Indeed, you will likely see more voice warning devices in the near future. We rely on these detectors to warn us, especially at night when we are sleeping. Awakening to this detector from a deep sleep helps orient you quickly by telling you the specific danger -- clearly and unmistakably. Notably, recent studies have shown that children can sleep through traditional smoke detector alarms, but will respond to voice warnings -- which this unit provides. Thus, placed in or near bedrooms this device can be a true lifesaver. Another favorite feature is ease of installation. It was a breeze and truly could not be simpler. A screwdriver is all you need. A small power drill/driver would speed the process, but is not necessary. Two screws into the ceiling or wall and you are done with the mounting bracket. The detector then just clicks in to place with a clockwise flick of the wrist. This is a do-it-yourselfer's dream. It doesn't get any easier! Battery maintenance is easy too as all you need do is turn the detector counter-clock wise a few clicks, and down it comes. You slide open the battery cover, take out the old batteries and pop in the new. Replace the detector back in the attached ceiling bracket, give it a slight turn and in it goes with a firm click. Done! Easier than screwing in a light bulb. Finally, the price is right! Under $40 for a unique life-safety device that is quickly installed and easily maintained. I have elected to use Energizer lithium batteries and replace them every 12 months -- with no problems. You may wish to change the batteries every 6 or 9 months. Duracells would also be a good choice. I personally would not use the cheaper, so called "heavy duty" batteries in a life-safety device. I should add that I would also suggest that if you have a home with multiple levels or an apartment with several rooms, having a separate stand-alone carbon monoxide detector elsewhere in the house as part of a total home plan would be a wise investment. Kidde also makes a fine combination model that protects against Carbon Monoxide and Explosive Gas. That unit, which has a digital display, runs on electricity and has a battery back-up system. It plugs in any electric outlet and can stay in the wall socket, or it can be placed flat on a table or dresser. I would also recommend Kidde's dedicated Dual Sensor combination Photoelectric/Ionization smoke detectors. These dual sensor devices provide maximum warning under fast or slow moving fire conditions -- conditions coming from a smoldering mattresses (slow) or drapery (fast) fire, just two examples. As one never knows what kind of fire could occur, these are the most versatile. Be sure to test your alarm regularly. REMEMBER that most Carbon Monoxide detectors NEED TO BE REPLACED about every 5 to 7 years (see manufacturer's guidelines). **This model has a built-in "end of life" function that beeps when the unit is 7 years old -- indicating it's time to replace it with a new one.** Similarly, smoke detectors have a useable life span as well. It's usually a little longer than carbon monoxide detectors, typically 10 years, but do check your manufacturer's guidelines. Hope this was helpful.

I have one of these Dual Detectors setup in my hallway and love it; its loud, simple to use, and with Voice alerts you know exactly what's going on. Other reviews detail these functions more in-depth so I wont waste time rehashing that info. What I want to warn others is the issues I encountered when I ordered a Second alarm. It arrived and immediately I noticed a slight issue; the battery door would slide open fairly easy. No problems, once it was mounted to the wall I wouldn't be touching the alarm so the battery door should stay closed. Once mounted I wanted to use the TEST feature to make sure it was all set - however no sounds came from the alarm. I jiggled the batteries and tried again; random beeps now and again if I tapped the alarm. Hmmm - maybe the included batteries were no good? So I decided to toss em and put in 2 of my own. However when I removed the batteries, they were red HOT. To the point that I felt like it was burning my hand taking them out. Once removed, I tried my 2 batteries - Same deal; alarm beeped randomly, batteries got red hot. I checked my first alarm that I had ordered earlier; still worked, batteries were cool as expected. So clearly this second alarm is messed up. I have sent it back to Amazon for a replacement and will update this review with my findings when the new one arrives. I will GLADLY rate this alarm 4 stars if the replacement works since the alarm is fantastic. Its just that my most recent one was DOA and getting batteries that hot cannot be good.... ---------------------- UPDATE ---------------------- I have returned my defective alarm and received a replacement. Amazon as always was easy to work with for returns/exchanges, so no issue there. The replacement alarm works just like it should. Great alarm, too bad I had to encounter a Dud first.

We live in a 4 level split home. Our gas furnace is on the lower, 3rd level. Two years ago we had several smoke alarms, but only one carbon monoxide detector on the top, bedroom level of our home. One early Saturday morning we awoke to the voice of this alarm broadcasting, "WARNING! CARBON MONOXIDE DETECTED!" over and over again. I got out of bed and took the batteries out of the unit. By then my then 16 year old daughter came out of her room and was watching me. I told her to go back to bed, but she asked me why we weren't going outside to our designated emergency spot. I thought I was being a bad example after all the years of telling the children to get our of the house if an alarm went off. I didn't think there was a problem. I assumed the unit was broken or needed a new battery. I wasn't thinking clearly. So, I put the batteries back in to see if it would go off again. It did. She again asked why we weren't following the rules and going outside, so we left the house and called 911. When the firemen arrived I kept apologizing for calling them to our home for an obvious mistake. I thought the firemen would tell us it was a false alarm. It wasn't. The heater core had cracked and was leaking carbon monoxide. The levels were high enough to make us confused, but not yet put us to sleep. Had my daughter not watched me handle the alarm I would have gone back to sleep without ever putting the batteries back in. We were very lucky to have my daughter and this CM detector. The voice made everything so much clearer than just a siren. If it hadn't said "carbon monoxide" I would have left the batteries out and gone back to sleep because I couldn't see any smoke or fire and I was tired. I don't think I would have thought about carbon monoxide. It was well worth every penny. I now have CM detectors on every floor of my home. This talking carbon monoxide detector helped save my families life.

I bought this detector on 10/17/10 from Amazon. The unit I received had a manufacturing date of 9/17/09 written on it. Amazon sent me a detector which was over one year old. These detectors have a life span of 5-7 years, so my "new" unit is already 20% used up. I hope that it won't have problems after sitting around in the warehouse for 13 months. Other than the manufacture date, this is a decent detector. It replaced an old KN-COSM-B whose batteries corroded and damaged the battery compartment. It's odd that they corroded, but the detector was 6 years old, so I gladly replaced it. Buy your detector from the local hardware store, who may have units which aren't a year old like Amazon.

THE GOOD: - It tested to work 100% as advertised. - It uses 3 AA batteries, not the less cost effective 9 volt battery. - The price was good. THE REASON WHY 3 AA BATTERIES ARE BETTER THAN 1 9 VOLT BATTERY: (Alkaline type) - 3 AA batteries cost 30% less than a single 9 volt battery. - 3 AA batteries have 1.5 times the stored energy as a single 9 volt battery. - The cost per energy available for 3 AA batteries is one half the cost for a single 9 volt battery. - AA batteries have a room temperature shelf life of 10 years, the 9 volt has only 5 years. - AA batteries are more available than 9 volt batteries. MORE ABOUT THE COST EFFECTIVENESS OF BATTERIES: (The following cost effectiveness comparison is based on the cost per energy stored in the battery.) - The most cost effective alkaline batteries (in "flashlight" type category) are the AA size for small devices and D size for larger devices. - The D batteries are 2.7 times more cost effective than the AA batteries. - The D batteries are 2 times more cost effective than the C batteries. - The AA is 2 times more cost effective than the AAA. - I try to stay 100% away from the 9 volt, AAA, & C. Note: - The costs used here are based on the big-box discount store prices, purchased in the large quantity containers. - The stored energy in the battery, used here, is based on published technical data from major, well-know battery manufactures.