CFM range for exhaust fan

[dkhaskins]

Hey all!

I'm asking for some recommendations on CFM ranges for exhaust fans.  I want to get one that is powerful enough to be usable with a speed controller but not overkill. 

Dimensions: 6"x7" with 6" duct
Air Flow: 240 CFM
Power: 37W
Voltage: 120V/110V
Decibels: 68 +/- 1.5
Attached Power Cord included


Thanks,

Darrell

[edtbjon]

The original AC fan is rated at around 230 CFM, but as it's AC, it's not very good for speed control. The recommended device for controlling AC fans seems to be Variacs, but there are other options too.

DCfans are better for speed control. There are DC equivialents fitting the Huky exhaust bowl etc. like this one "PM240-24D-1751B-2TP" which you can find on e.g. EBay. (It's PWM controllable, so using an Arduino (or cheaper clone) connected to Artisan makes it controllable from the Artisan interface.)
This is all discussed in this thread and also in this thread.

[hankua]

My 800n pro style coffee roaster has a 95cmf blower/air fan. The inexpensive inline blower would probably work if connected to a blast gate. How to fine tune the setting is a question however.

These are the type of air fans found on small commercial roasters:

http://www.blower.com.tw/page/product/show.aspx?num=233&kind=100&page=1#cy100

[edtbjon]

I tried to send them an inquery about the smallest fan. It will be fun to see what the answer is.