fire box opening size

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Smoke Blower
Original poster
Dec 21, 2016
Hello all
I started a reverse flow build out of a air question is that my tank is 16 by 40 and using feldons calculator it says that my fire box opening should be ..opening size 6" and half moon size 8.5"so when I was laying out for the door and if I put the bottom of the door at the half way point of the tank that would be at 8"and the height of my half moon would be at 6" that gives me 2" in between my cooking grates ..I would like to lower my door down further maybe a inch or two below the center of my tank.I was wondering if I lowered my fb opening size down to say a 1" so my opening would be 5" would I just add that inch to the half moon size.. is reader supported and as an Amazon Associate, we may earn commissions from qualifying purchases.

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