The sketch is fine. I believe that this would do the trick. You just need to be careful not to put a fan that pulls more CFM than your hood. Of course, keep in mind the thing about replacement air if you’re in a small space that is airtight. And do wash your range hood filters often and check the inside when you remove them. My range hood is still pristine. The fan will be a problem, since you’d have to clean it after each session. Maybe you can place a piece of cloth range hood filter somewhere before the fan, but nothing too thick. Nevertheless, you’ll need to clean the fan often if you want it to last.
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braca. Thank you so very much. This was extremely helpful. I will follow the above and start roasting. I just got my 3D exhaust adapters and can’t wait to get the whole set up ready.
Again, much obliged.
Have a great day.
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Just to share a brief update on my setup, which I also intend as a help to @mocha.heights, the gentleman who installed the ventilation for my setup came over yesterday and asked to do some roasts so he could figure out what was going on. The short answer is that he is stumped. On the one hand, there is excellent air flow and plenty of smoke coming out of the vent hood outside, even with only one 6" AC Infinity S6 Pro. On the other hand, during first crack and beyond, the smoke seems to envelop the entire back of the roaster. His theory is that the roaster is producing more smoke than the ventilation can vent during this time.
We discussed possibly switching to 6" or 8" metal ducting, adding a kitchen vent hood over the roaster, and getting rid of the elbows as suggested above, but he prefers to research more and figure things out before throwing money at the problem.
In the meantime, I found a lovely metal kitchen island cart at home. I will put the Bullet on that and get a laptop arm affixed to it so I can roast outdoors easily.
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Thanks much for sharing inbabouna. I’m very interested and will be keeping an eye to see what he finds out. If you can share with us the results of the research I will really appreciate it. My problem is that I installed the 220V in the basement close to the circuit breaker, and there are no other 220v outlet as we only use 110V in the US.
Again, thanks much for sharing.
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Here is an air quality graph captured from my roast yesterday. The first blue vertical line is when the beans were added to the R2 Pro and the second line is when I dropped them. You can clearly see the PM2.5 does spike after the beans are dropped but quickly goes back to baseline.
More relevant to this discussion, there is not any significant PM2.5 detected before the beans are dumped out of the roaster.
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Well, that’s either negative air pressure, or a gust of wind moving the smoke before it gets expelled. It is very difficult to have certainty without being there, but as things stand, I’d go with negative air pressure that pushes some smoke back.
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Yeah, exactly the same as my situation. You know, there’s an annual fair being held here and they place a deep fryer under my window with the exhaust just going outside of their kiosk. If I open any window, I get much higher readings than those. Of course, we don’t pay much attention to everyday stuff, but if you were to use your meter during cooking or any kind of burning, you’d become very paranoid. I’ve burned the tiniest piece of thread that was sticking out, with a lighter, and the meter went crazy and back to normal very soon. What I’m saying is that your readings are exactly what they should be and I don’t see them as much more of a risk than our various daily activities.
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Yes @braca19452f9m, I agree that short lived spikes in PM2.5 are very typical with lots of daily activities, especially cooking. I have a monitor in our kitchen so I see what happens every day when we fry eggs or make toast. As long as the levels fall back down to a reasonable baseline, I don’t worry about it. I do admit that I will hold my breath for a 30 seconds when I drop coffee beans just to avoid a big whiff of bean exhaust 
I mostly just wanted to show @ibnabouna that I don’t think it is normal for the R2Pro to emit significant particulate prior to dropping the beans. This points to an issue with his ventilation and/or the AQ meter.
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Hey @ibnabouna, just thought of the 3D exhaust adapter. Did you install that? Maybe that helps if you don’t have.
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