![First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup - Combination Smoke Carbon Monoxide Detectors - Amazon.com First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup - Combination Smoke Carbon Monoxide Detectors - Amazon.com](https://m.media-amazon.com/images/I/71bOL6iOrqL._AC_UF894,1000_QL80_.jpg)
First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup - Combination Smoke Carbon Monoxide Detectors - Amazon.com
![Seattle Fire Dept. on X: "Is your carbon monoxide alarm chirping every 30 seconds or so? That signals that it's time to replace it. CO alarms have a life expectancy of around Seattle Fire Dept. on X: "Is your carbon monoxide alarm chirping every 30 seconds or so? That signals that it's time to replace it. CO alarms have a life expectancy of around](https://pbs.twimg.com/media/FIThSUQVgAId9d6.jpg:large)
Seattle Fire Dept. on X: "Is your carbon monoxide alarm chirping every 30 seconds or so? That signals that it's time to replace it. CO alarms have a life expectancy of around
![Need help with this carbon monoxide detector as getting problems and its chirping/ showing yellow light. Detector model is a BRK CO850MBXi. Full description of problem in comments. Any help would be Need help with this carbon monoxide detector as getting problems and its chirping/ showing yellow light. Detector model is a BRK CO850MBXi. Full description of problem in comments. Any help would be](https://i.redd.it/h6sbmfw4p1m71.jpg)