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jyl jyl is online now
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Join Date: Jan 2002
Location: Nor California & Pac NW
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So, step one, how much exhaust airflow?

Assuming 36" commercial range w/ salamander broiler, hood 42" on sides and 60" on front (so, about 12" overhang on sides and about 8" on front, both range and hood mounted against the back wall, with full side panels.

I used two methods. One is a generic calculator - for hood of circumference c, mounted at height y above source, to achieve capture air velocity v, what is airflow A. The calculator recommends v >= 0.2 m/sec. With no side panels, using c = 3.7 m (just front and sides), y = 0.69 m, calculator says I need A = 3,310 cfm (!). Not sure how to incorporate the side panels, but I decided to subtract them from circumference, leaving c = 2.6 m (one side panel) or c = 1.5 m (two side panels). Get A = 2,400 cfm (one side panel) or 1,500 cfm (full side panels).

Exhaust Hoods

Another is a commercial kitchen ventilation design guide. This factors in the volume of contaminated air Qc produced by each type of cooking equipment, area A of equipment and of hood, etc. Combining the Qc of a gas range and a salamander, using A = 36" x 33", and hood area 42" x 60", I get 1,400 cfm. Adding the factor for side panels, I get 1,260 cfm.

http://old.greenheck.com/pdf/kitchen/KVSAppl&DesignSeptember2005.pdf

I figure the generic calculator is not designed for cooking equipment (which produces heated contaminated air, which naturally rises), so I'll use the second result.

Jeez, this is already a lot higher than I expected. Hardly any residential exhaust hood/fan goes above 1,000 cfm.

Anyway, on to step two.
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Last edited by jyl; 01-30-2011 at 08:26 PM..
Old 01-30-2011, 08:24 PM
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