Temperature at fan / vent bowl

[phischmi]

Hi all,

has anyone yet measured the max temperature at the vent bowl?
Either the material (bowl/thief/funnel) or the exhaust air temperature at this point.

I'm thinking of 3d-printing an adapter for a smaller fan and need to know the max temperature in order to choose the right material regarding heat resistance.

I appreciate any answer

Thanks all!

Philipp

[edtbjon]

I measured it once (for a couple of roasts) at the exit of the vent bowl. I wanted to find out which kind of exhaust tubing was needed in terms of how much heat the tube needed to take. It maxed out at around 70C/160F (which I found low, but I redid that measurement a few days later with the same result).

[phischmi]

Hi,
thanks for your reply!
Did you measure exhaust air-temperature or surface-temperature of the vent bowl?

[edtbjon]

I measured it with a small flexible probe (which came with my Center 301 meter) in the very center of the 2.5" exhaust of the bowl. There is a thread about it here: https://www.hukyforum.com/index.php/topic,77.msg563.html#msg563.

[day]

I will get some measurements of mine later but, after I cut a hole in the table and sealed all of the gaps it gets significantly hotter now! The outside vent is now as hot as the bowl used to
Be before proper sealing, so it may well depend on how tightly you have installed the system.

[phischmi]

I will go for 3mm of PA12, which is Polyamid, for printing my adapter. Should do the job

Thank you guys!

[day]

ill try to take a temperature reading soon for future users that may need the info. I just finalized my vent set up. I could have made it prettier, but just decided to rely on tape. As of right now I am not capping the funnel, just closing it, but havent decided if it would be better to cap it to maximize usable fan speed range and maybe reduce variations in performance.

i drilled a hole in the table and mounted the fan (didn't want to buy a 7inch hole saw so just used a six and then widened , then drilled a hole in the funnel and put in a quick vacuum port. This allowed me to tape the funnel to the mesh screen and thereby significantly improve consistency and easy of use. After a couple hours of testing various aspects of fan usage I found that even the smallest of cracks or error in placement could cause significant changes in roast performance at specific gas settings. All moving connections were pressure fit by wrapping with aluminum tape until barely able to slide into position, pretty much eliminating stray  air. After doing all of this, the vent gets significantly hotter! Much more efficient, increased my usable fan range, and  definitely increased consistency, but i may need to actually get a better ventilation outside now, as I didn't originally install it with the outside air vent getting too hot to touch. May damage my siding now...or cause a fire

[hankua]

So this is a semi-permanent solution to chaff collection?
Excellent idea a far less complicated than the woodworking chaff collector!