I didnt try shutting the air inlet to see if it would pull back in. The chimney is about 16' tall, it sticks above the peak of the garage 3-4'. There are two bends in the chimney, after it leaves the stove about 3' up there are two 90 degree bends and then its a straight shot through the roof. I cant install any cord seal in the door because it just sits flat when shut, there is no edge for the seal to go into, poor design on my part but this summer im going to make a new door. If i open the door the flames dont leap out but the smoke flows out steadily into the room. I will take some pictures tomorrow because i feel like there is a simple flaw in my design that i just cant see.