Second hole in block chimney?

My Tarm Solo 30 smokes unacceptably when I have to open the door with a fire going. I bought a draft fan to install on my stovepipe, but my sections of pipe are too short to do a good install. I'm left with two choices - move my furnace at least 6 inches or so, which involves quite a few piping connections, or possibly install a new hole in my chimney to give me a greater run. The chimney is built of 8" concrete blocks, and I have 3 and a half blocks between my present port and the ceiling. If I skip a course, can I knock a new hole 16" above the present one?

BoilerMan said:

How far from a combustible surface (wood) will that put your flue pipe?

TS

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The closest wood is the bottom of the 2x10 joists for the floor above. The present port was split between the 4 and 5th full blocks down from the bottom of the joists and there is a half block at the top as well, so the top of the present pipe is 35" below the joists. Each course above, were I to split the blocks again, gets me 81/4" closer. It seems like I should probably leave at least one full course in between, in which case I would end up about 18" down. Of course, I don't know anything about masonry, which is why I'm asking.

Fred61 said:

I think they suggest mounting the draft fan on a horizontal section of the smoke pipe.

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This would definitely involve moving the boiler, as the chimney just doesn't have any room to move.