High Efficiency Gas Furnace Combustion Air Intake

Fortunately you are correct that your new high efficiency furnace should have an integral combustion air intake duct that supplies air directly to the combustion chamber.

High efficiency gas furnace combustion air intake. Department of energy a defining feature of high efficiency furnaces is sealed combustion a process by which outdoor makeup air is piped directly into the burner. This means the furnace does not take air already heated by the furnace and use it for combustion. Check to see if the furnace combustion problem is caused by an obstructed air supply pipe by removing the burner compartment cover. This will provide free airflow to the combustion chamber.

Other aspects of high efficiency furnace venting there are several other important aspects of high efficiency furnace venting. Since high efficiency furnaces draw air directly from outside the furnace itself does not require a fresh air intake in order to replace inside air. An obstructed air intake vent pipe in a direct vent two pipe system will cause serious combustion problems in a condensing furnace. This high efficiency venting system must be installed when you install the new furnace.

The pvc pipes are used for air intake exhaust gas and to remove the corrosive condensation resulting from the combustion process. However condensing furnaces can also be installed as single pipe non direct vent configurations in which the combustion air is drawn from the indoors. Due to high efficiency furnaces having their own fresh air intake no air is drawn from inside your home.