An illustrative example monitoring system includes a carbon monoxide sensor configured to detect carbon monoxide within an area, a heater situated near the carbon monoxide sensor to regulate a temperature of the carbon monoxide sensor, an ambient temperature sensor configured to provide an indication of an ambient temperature in the area, an occupancy sensor configured to provide an indication whether the area is occupied by at least one individual and a controller. The controller is configured to determine whether the ambient temperature in the area is below a threshold based on the indication from the ambient temperature sensor, determine whether the area is occupied by at least one individual based on the indication from the occupancy sensor, and activate the heater when the ambient temperature in the area is below the threshold and the area is occupied by at least one individual.