Indoor Air intake question

[SHRED]

I am trying to get a handle on the hear from my new 315 lec light in my small area...2.5'x2.5'x5.5'.

I just upgraded from a 4" 150 cfm Vortex fan to a 6" 315 cfm Hyper Fan. I'll need to get a bigger charcoal filter. I tried running a reducer to the 4" filter but it howled a little too loud for my liking.
I have a hard sided grow space.

Questions are...What size intake port do I need? More than 6" diameter intake port to get maximum airflow for this 6" fan?

 

[A-Train]

Do you have a speed control on your new fan?

 

[SHRED]

Do you have a speed control on your new fan?

Yes. I'm running the fan wide open so I didn't install it.

 

[A-Train]

Ok I'd you put a 6 inch intake you'll proably have to keep running it full speed... but if you make the opening larger than 6 you could most likely use the speed control as a temp control in your tent... according to the quality and temp of your intake air

 

[SHRED]

Ok I'd you put a 6 inch intake you'll proably have to keep running it full speed... but if you make the opening larger than 6 you could most likely use the speed control as a temp control in your tent... according to the quality and temp of your intake air

Thanks.
I just read over at growweedeasy that passive intake volume should be 3 to 4 times larger than the exhaust pulling it.

 

[SHRED]

I found this. A 300 cfm fan needs the equivalent of 1 sq ft of intake.

http://www.greenpassion.org/topic/16793-what-size-vent-fan-do-i-need-and-intake-area-size/

 

[SHRED]

One of my biggest mistakes learning indoor growing is under ventilating. I'm still playing catchup.
I've settled now on a 6" Hyper Fan @ 315 cfm, a 6" "Skinny" Phresh filter, and 1 sq ft of passive intake.
I'll be testing it out soon.

 

[Bamba]

there is a way simplier way to find out....
You put your fan on full power
You start open your intake hole and checking your tent
As long your tent`s walls are sucked in you are ok when they start to lose you stop opening the intake hole.
You want the sweet spot where the walls are sucked in but not too much to put stress on the fan.

You also want negative pressure so all smelly air pass from the filter.

 

[camo420grow]

Are you talking about suckling thru the charcoal filter outside the tent in taking into the grow area? I guess I'm not understanding how you will make the intake bigger if the fan is suckling thru the charcoal filter

 

[Bamba]

EDIT

You need 2 holes/openings

1 will be the passive in take or you could add one FAN in front of it.
2 will be the hole where you mount your extraction FAN/turbine, that is linked to your carbon filter and blows the air in it and out in the room.
2b you hang the Carbon on the ceiling(so it ll suck the hot air that is gathered up there) and then extraction FAN/turbine, that will suck the air from the carbon and out of the tent.

option B is more noisy because the filter after the fan works as a silencer for the air noise and requires a strong tent to handle the lights the carbon and the fan.