Carbon Monoxide is a colorless, odorless toxic gas produced by furnaces and boilers during the combustion process. This gas is especially dangerous because its presence can only be detected by specialized instruments. You can't see it or smell it.
Inefficient combustion, such as that caused by furnaces and boilers with components that are dirty or out of adjustment can create elevated levels of Carbon Monoxide in exhaust gasses. Carbon Monoxide can cause sickness, debilitating injury, and even death. Carbon Monoxide detectors are inexpensive and installing one in a home with a furnace or boiler is recommended. Detectors should not be placed next to heating appliances like furnaces and boilers but should be placed to protect living and sleeping areas.