If you have an AC/Heater unit, gas or wood burning fireplace they along with other things like portable heaters, water heaters, kitchen stoves, clogged chimneys can be a common source of Carbon Monoxide in your home, so it is a good idea that you also buy and install a “Carbon Monoxide Alarm” carbon monoxide is a silent killer and has no smell. The alarm looks just like a smoke alarm and they run from $25.00 to $100.00, but at least the cheapest one is better than nothing. If you don’t have one, you should consider buying one, it might save your life or the lives of your loved ones.