by matt walker » Thu Feb 20, 2014 6:09 pm
Yeah man, great job there! So good to see you and your progress. What Manny said, you are almost there, and what you are going through is completely normal, so don't get discouraged! You won't have smoke in the house once you get it dialed in, I promise.
So, a couple things. First, you are going to have to go up with the chimney quite a bit higher than you are right now. Ideally, you'd have insulated chimney going higher than the highest point on your roof. Insulated chimney is crazy expensive, so if I were you and didn't want to spend the cash on the expensive chimney I'd start sourcing sections of single wall ducting and going up as far as you can. A chimney cap will keep the rain out, don't turn the exit back down. Down the road you will want to get the chimney up above the roof line so you aren't subject to wind driven pressure differential, but in the mean time you can start to improve performance incrementally by adding sections as you get them. For better performance, the outside chimney should be insulated. It will never be hot there, so you can box it in with wood and insulate with fiberglass or perlite or something, but that can probably wait until you get a little farther along.
Secondly, the exposed horizontal ducting is cooling the gasses way more than they will be cooled once it's all cobbed. That rapid cooling to below condensation point is a big part of your troubles. Heavy, wet, dense cold exhaust is really hard for the heater to push out. Keep cobbing, keep burning, use your fan to overcome this stage. Once you have it all cobbed in and the cob is warm, it will be WAY better. My home heater is a bear to start when it's cold, but ideally that only happens once a year. You will most likely have the same characteristic with yours, so be aware of it, and again, you can use your fan to overcome this stage.
A feed cover is a huge help, as Manny says. I like a pot turned upside down, I posted a pic here somewhere, hold on.....
Like so...this way the smoke is captured and sucked back in to reburn...
I'm confident you will get to the point that it will run perfectly without the fan just by having warm, dry mass and a vertical chimney, so I say, keep going man!