The carbon monoxide alarm has a short beep every so often is that normal with the plug in and where would you suggest putting them

Hi YoYo, If your detector is chirping once a minute, this would indicate low or missing battery warning. This detector requires a standard 9 V battery for emergency backup. If this is not the case, please feel free to contact First Alert Customer Support at 1 (800)-323-9005 and we will be happy to assist you. You can check our recommendations for detectors placement here: https://support.firstalert.com/s/article/Proper-placement-for-smoke-alarms-CO-alarms-and-fire-extinguishers - Maria