How to calculate size of booster fan in long duct run

I have heard of using booster fans to increase the effectiveness of but I can't find much info on them. My run is 16 feet long with four air cooled hoods with 6 inch ducting and a carbon filter. The end of the run that is pulling air in seems very weak and I want to increase the flowof air but don't want to get a bigger noisier in,one fan if the job can be done with my smaller fan and a booster. Any help would be appreciated.

i assume u have a vortex or similar 6" fan. Any booster fan should work fine with this and greatly improve the flow. Boosters r a lot more quiet and move a lot less air, but any size will help with your run.

Booster fans go in the trash at my house.

- Jiji

A booster fan is often more of an impedance.

One tip, your centrifugal blowers CFM likely exceeds the 6" ductwork rated capacity.

Yes a booster fan will give you back some of that strength back, what i would do is move the inline up closer to the hoods and use the booster at the intake, also would get a 6"-8" adaptor and use an 8" booster for the extra power

Booster or inline fans arent even worth a shit boosting output from a heat duct where the draw is only restricted by a flimsy furnace filter , in my big room i run 3 hoods per table daisy chained together , at the start of the chain i have large can carbon filter with an 8 inch fan mounted directly on top of the filter which is 10 ft from 1st hood , 1 ft from 1st hood i have a 6 inch pulling air from the 8 inch then pushing into the 1st hood , at the end of the hood chain i have a 2nd 6 inch fan pulling hot air from the 3 hoods that are being fed via 1 6 inch & 1 8 inch , my glass is so cool i let the canopy grow up into the glass very hard durring the 1st month to maintain perfect canopy level with zero leaf burn , even in july & august .

I tried the booster fan deal & the only thing boosted was the cash from my wallet , now ive got 8 useless booster fans on top of my pile of unused gear , run another vortex & put a muffler on your exhaust , or run it 3ft underground like i did .

Frankly 4 hoods is a little beyond capabilities of a 6" single run in series.

Probably best to put 2 parallel runs, each consisting of two 6" hoods into an 8" trunk and run an 8" centrifugal blower.

i used a 8 inch vortex to cool 5 1000w's, u may just need a second vortex 6". put one right outside the room and the other at the end of the run.

I really wish I had hoods with 8 inch ducting but I don't so I have to stick with the 6. I can't do 2 separate parallel runs because of space constrictions. The comments here are kind of confusing as to what you are trying to say.....
Right now I have

Hood>>>>Hood>>>>hood>>>>hood>>>fan>>>filter

The fan is sucking air through the hoods amd pushing through the filter. I know pushing though the filter is not ideal but the hoods don't seal enough to do otherwise. Any suggestions to improve my current airflow would be awesome

jjohns93 said:

I really wish I had hoods with 8 inch ducting but I don't so I have to stick with the 6. I can't do 2 separate parallel runs because of space constrictions. The comments here are kind of confusing as to what you are trying to say.....
Right now I have

Hood>>>>Hood>>>>hood>>>>hood>>>fan>>>filter

The fan is sucking air through the hoods amd pushing through the filter. I know pushing though the filter is not ideal but the hoods don't seal enough to do otherwise. Any suggestions to improve my current airflow would be awesome

Click to expand...

You could spend 10 dollars on weatherstrip seal to fix your hood seals.

- Jiji

Buy a variac that lets it go beyond your normal voltage limit - turbo boost that fan.......