What is the difference between Direct-Vent and B-Vent?
A B-Vent gas appliance uses the concept of natural draft to expel the combustion by-products. Air is being pulled up the chimney or flue by means of draft which is caused by the tendency of warm air to rise. The draft leaving the stove causes air to be pulled into the fire chamber from the room. B-Vent products would only be used when an existing chimney is available. Direct Vent gas appliances use a double walled exhaust pipe. This pipe has a center portion and an outer portion – co-axial design. The exhaust leaves the stove through the center portion and forces replacement air to be pulled in through the outer portion of the pipe. The need for vertical rise is not as great since the air coming in is from the outside environment. Direct-Vent appliances can be vented with as little as 3 of pipe and a 90 degree elbow.
