topoftheriver
Member
The external chimney pipe damper is the key damper. Some fire departments who perform the inspections in various localities, especially in Mass want the damper installed for what they call safety. I can't be sure if it is in the code but I have one. As I previously stated, it helps in extremely high winds. It is not my intent to be an authority on this subject but merely to express some views. They get quirky here in New England. I also have a place in Maine and to my knowledge I believe they call for it there. I have one on the chimney pipe in my hunting lodge. On that mountain we get high winds as well and it does help when adjustments need to be made.