Ventilation Question

[Guest]

My grow room is going to be 3x3x6 ft. Im going to have a 400 watt HPS running in it most likely doing a scrog technique. my question is, what kind of exaust fan and what kind of rating CFM should it have? Eventually I'll be connecting a carbon filter.

Would a bathroom exaust fan work well enough? Please let me know thanks

 

[Guest]

Was wondering if this would be enough, suppost to have a 170 CFM rating
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7539353455&sspagename=ADME:L:RTQ:US:1

 

[Guest]

When you hook the carbon scrubber up you'll probly want more cfms than that. I would get a 265cfm raiting. More $$ but it will def help keep the temps down. Peace and *bong* :friends:

 

[big bud]

something like this

http://cgi.ebay.de/Aktivkohlefilter...itemZ5994793745QQcategoryZ25835QQcmdZViewItem

 

[cough_cough_eer]

My room is a little larger but I also have the 400 watt and a scrubber. I had a 170cfm fan and it just didn't keep the temp. down at all. go for the 265 CFM :smile:

 

[Guvnor]

To achieve an air change 2-5(?) times minutes in your growspace, something in the region of 200cfm +. But with the resistance put on the fan by ducting lengths and carbon srubbers,even thou not alot will cause the fan to loose cfms. The 265cfm exhaust others have suggested sounds about bang on, the extra cfm's will compensate the loose from the scrubber, length of ducting etc...

The air taken away by the exhaust must be replenished with fresh air (about 70degrees, would be nice) so enough intakes must be installed to serve this.

Guv'nor

 

[Guest]

So you don't think a passive intake would be sufficient?

 

[Guest]

Also I was thiking of getting this 300 CFM 4" Duct fan, is there a good way that I could possibly make it less noisey?

 

[bartender187]

^^^
snakin around extra ducting will make it less noisy, but will also cut down on your CFM alot....

Passive intake/Active exhaust... only way to go IMO....

for a 400, 170cfm INLINE would be plenty. i have a 250cfm on a 600watter and its cool to the touch.

make sure your intakes are at least 1.5x the size of your outtake hole. backpressure will lower your CFM as well.

 

[Guest]

Well i don't plan on building my carbon filter till i'm ready to flower. I'm sure its different indoors but I have outdoor plants that i can walk up to touch them tap them, and i dont get a huge smell off them. I do plan on building the filter just not right away (basically im low on cash)

I was going to put 1-2 small ocsillating fans inside the box and an exhaust fan, just not sure what kind yet.