Hood vent question

[Jako]

Building a new house and today we picked options. I am having a brewery built out and my builder is asking me how much air the hood needs to flow. I'm running gas and the brewery will have no windows. Do I need outside being pulled in and how much flow must the hood vent flow?

 

[day_trippr]

Batch size?
fwiw, I do 10 gallon batches with a 3v2p single tier herms with 8" ducting positioned to pull the steam from HLT and BK and driven by a 650 cfm blower. It's just adequate as is and that's with the ducting focused on the two heated kettles. I suspect the ~6' x 3' hood I'd need to capture exhaust heat and steam would result in such diffused reduced velocity airflow that it would be a step backwards vs the focused ducting I've been running for the last year.

I need to do some experimenting with a temporary (read: cheap) "hood" to see if it would actually work well enough to commit to fabricating an SS version.

btw, I do need to open windows else that blower will pull air down the chimney flues - not good if the oil furnace is running. An automatic make-up air damper is clearly called for and I actually have been considering installing one.

Cheers!

 

[Jako]

Thank you for the detailed reply. I currently do 5G but I wouldn't doubt that one day I would upgrade or push my system and do a 10 gallon. My builder said anything over 450 would require a vent to pull air in so it didn't create a vacuum. I wonder if I should do two small vents with high flow like you said.

 

[Bobby_M]

Side question. Why wouldnt you convert to electric while you have the perfect chance to spec out the appropriate circuit now for cheap? Big mistake.

 

[Jako]

Side question. Why wouldnt you convert to electric while you have the perfect chance to spec out the appropriate circuit now for cheap? Big mistake.

Thought about it but I had just bought new gear for gas. Also I read gas is more efficient and easier to clean. But you are making me second guess my decision now.

 

[day_trippr]

Assuming fully immersed heating elements electric is more efficient because all of the energy goes into the product. Indirectly applied energy such as gas fired and stove-top electric are less efficient because heat is spilling around the kettles or is otherwise lost...

Cheers!

 

[Jako]

Assuming fully immersed heating elements electric is more efficient because all of the energy goes into the product. Indirectly applied energy such as gas fired and stove-top electric are less efficient because heat is spilling around the kettles or is otherwise lost...

Cheers!

I should have been more specific, efficient as in cost to run. and on a larger scale i believe Gas is best until you move to steam jackets ect.

 

[day_trippr]

Where I live the only chance the math would work would be using natural gas as propane goes for around $4 a gallon in the typical 20 pound (bbq) cylinder, and I burn a half tank doing 11 gallons to the fermentor. Otoh 14 cents per KW for sure electric would be way cheaper per batch here...

Cheers!

 

[Bobby_M]

Thought about it but I had just bought new gear for gas. Also I read gas is more efficient and easier to clean. But you are making me second guess my decision now.

Exact opposite. Electric is better in every way especially for brewing in doors. I spend $1.50 per brew day for energy. Kettles are easier to clean. Better, more responsive temp control. Less overshoot. Safer to leave unattended for periods of time. Faster heating.

 

[Jako]

Exact opposite. Electric is better in every way especially for brewing in doors. I spend $1.50 per brew day for energy. Kettles are easier to clean. Better, more responsive temp control. Less overshoot. Safer to leave unattended for periods of time. Faster heating.

Well shucks