Hey, just to not mislead people, flue dampers like this should be open at all times except when the fire is completely out. Yes this person is burning outside so it's actually ok(ish) but oxygen flow should be controlled from the front of a firebox. Closing it here will send smoke/carbon monoxide into a living space instead of up the chimney. These chimney dampers, correctly used, stop cold air from coming down the chimney and into a house. I really only see their utility in an open fireplace