The Kidde KN-COSM-B costs less than interconnecting models that protect homes from CO and flaming fires. The typical horn alert is followed by a voice warning that announces whether a fire, carbon monoxide or low battery is detected. Some drawbacks: It doesn't offer protection from smoky, smoldering fires and it has no digital display that monitors CO levels. It has a five-year warranty, and the CO sensor may last up to seven years. Consumers looking for a reliable, interconnecting CO detector should consider the highly rated First Alert Onelink SCO501CN (*Est. $75).
We didn't find expert reviews on the Kidde KN-COSM-B, but owners highly regard it at Amazon.com and HomeDepot.com. We also found a useful comparison chart that rates nearly 200 detector models on key features at AlarmSpecs.com.
The Kidde KN-COSM-B is among the CO detectors that get the highest reviews at Amazon.com. More than 70 owners give it an average rating of 4.2 stars out of 5. They agree it's easy to install and use, and many report the alarm worked flawlessly.
Review: Kidde KN-COSM-B Battery-Operated Combination Carbon Monoxide and Smoke Alarm with Talking Alarm, Contributors to Amazon.com
HomeDepot.com sells approximately 20 carbon monoxide detectors online, but very few have accumulated reviews by owners. The Kidde KN-COSM-B is the highest rated with 4.7 stars out of 5. Reviewers particularly like the voice alarm and say it went off without a hitch when smoke or CO was present.
Review: Kidde Battery-operated Voice-alert Carbon Monoxide and Smoke Alarm, Contributors to HomeDepot.com
This single-page site rates nearly 200 models of carbon monoxide, heat and smoke detectors based on lifesaving features. No detector receives a perfect score of 12, but the highest rating of 5 goes to three combination detectors. Editors favor the Kidde KN-COSM-IB and two combination CO and explosive gas detectors: the First Alert GCO1CN and the Kidde KN-COEG-3. There's no narrative evaluation here, and ratings are based solely on features.
Review: Alarm Specification Comparison, Editors of AlarmSpecs.com