Why Is it Important for Your Home Furnace to Have a Complete Combustion Reaction?

Importance of Air

• Complete combustion of any fuel requires lots of air. For example, complete burning of one cubic foot of natural gas requires 10 cubic feet of air. This means your furnace needs a steady source of fresh air while in operation. The furnace will draw its air from your house unless the furnace has its own separate outside air inlet. The main byproducts of complete combustion of fuel and air are carbon dioxide, water vapor and some traces of oxides of nitrogen. If your furnace isn’t getting the proper mixture of fuel and air because of a mechanical malfunction or insufficient ventilation, it will produce lots of deadly carbon monoxide that can build up to a point where it can injure or kill you.

Carbon Monoxide

• Carbon monoxide gas is colorless, odorless and tasteless, but deadly. Symptoms of carbon monoxide poisoning include persistent, severe headaches that often affect multiple family members. The headache typically is accompanied by nausea, vomiting and a general feeling of weakness and confusion. If you experience these symptoms, leave the house to see if they clear up. If they do disappear when you are away from your home, you should suspect carbon monoxide and call your fuel supplier or heating technician to have your furnace checked.

Preventing Problems

• You should have your furnace inspected by a heating technician each year before the heating season starts. The checkup should include cleaning and adjusting the burners, changing fuel and air filters, and lubricating motors and controls as prescribed in the furnace maintenance manual. You also should install carbon monoxide detectors on each floor of your home that will sound an alarm when they sense the presence of this poison gas. Most household carbon monoxide detectors plug into a standard electric outlet or can be hard-wired into the house's electrical system.

Trouble Signs

• Certain symptoms in your furnace should be checked out immediately by a technician. Any abnormal rumbling or popping noises from your furnace should be checked out. Properly functioning burners have even vertical or horizontal flames. If your flames are uneven or lean markedly in one direction, you may have a dirty burner or cracks in the furnace. The fine black powder known as soot is a symptom of incomplete combustion. If you see soot in your combustion chamber, you may need your burner adjusted and your furnace checked for cracks in the heat exchanger. Repetitive short cycles of under three minutes indicate a thermostat or burner is out of adjustment.