Vertical Exterior Flue Pipe?

Hi Everyone!! We are awaiting the arrival of our Glowforge and I’m trying to get everything set up so we can hit the ground running.
I have read that the exhaust duct needs to be as short as possible but was curious if a vertical flue outside would seem like a bad idea to anyone. Seems to me that the draw from any rising heat would only increase air flow but I may be overlooking some detail I am unaware of. The vertical flue is to get the fumes/smoke above street level behind our building which is located downtown…
FYI- My intention is to use the ac infinity 6" fan as we will be using this in a room where we also store our huge inventory of blank tees for printing and my hope is to have no residual smells lingering in my apparel.
Any advice greatly appreciated!!


I can’t say that vertical would be better or is preferred over regular venting, but I’ve been running my exhaust up a chimney for 4+ yrs and it’s worked fine. I only have the hose about 18" above the damper, and before adding an inline fan a few years ago, I only had a handful of days in 105 degree weather where it didn’t vent quite as well. Since adding the fan, no issues at all and it works very well for me.


I agree that it shouldn’t be a problem, but I WOULD recommend something along the lines of a sanitary T, but used upside-down, sealing the “bottom” with a cap. This will allow you a kind of trap to access and occasionally clean out any debris that doesn’t make it all the way up…


As long as the vertical section is kept short enough for the fan to push the air column in the vent, it will work. (Likey 10’ OK–30’, not ok!–lots of info available on the internet about this, even if look under dryer venting…) .

I’ve not added one for my GF yet, but just installed one for venting my basement apartment’s bedroom, and did some quick HVAC math to decide on size I needed… (and options for my GF).

And don’t decrease back down to 4"–I’ve read lots of folks doing that, but actually that can be bad for the fan–increases friction since the 6" diameter is now forcing that air back into a 4" diameter and can compromise the life & increase noise a bit–but the AC Infinity is great, no matter what size fan/ducting!

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I appreciate it, but I just run my insulated hose up the flu and it fills most of the opening anyway. It’s not technically sealed, but the small amount of gunk that falls down just lands on top of the mostly-closed flue where I vacuum it up on occasion. Even then I rarely find anything, so my motto is, if it aint broke, I got other stuff to fix. :stuck_out_tongue:


Thank you all for the input!!

This question is outside our team’s scope. I’ve moved it to the Beyond the Manual so the discussion can continue there.

Well, there was that lunatic in Colorado

Three years and still going strong!


Good suggestion

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