Our smoke and carbon monoxide alarms perform between 40 degrees and 100 degrees Fahrenheit.
This is usually caused by the absence of AC power to the smoke alarm.
Combination alarms save space in your home, and they mean you only need to test and change batteries in one device rather than two.
Any time a digital unit displays a number with or without an alert, assume it senses carbon monoxide. Leave the home and call 911.