Correct size extractor fan

[nznene]

hi youall 😊
i have a new grow tent
2m x 2m x 2.3m high
can some please recommend the right size extractor fan
6" or 8" ??
Thank you

[Smokesteve]

What wattage light will you be using? Actually draw at the outlet please.

[nznene]

Ahhhm
I have lots of light
2 bars 600watt w 3 pucks on each
1 400watt w 2 pucks on each
1 vipar spectra 600watt

And we also get alot of humity ..with cold and hot weather

Thanks for your help 🙂

[ChadWestport]

6.5 x 6.5 x 8' = cubic feet of room = roughly 340cubic feet. You need a fan that has a rating of 340 CFM (cubic feet per minute) to exchange the air once per minute in your tent. I'm not positive off the top of my head, but I think you want to exchange the air at least every 3 minutes.... might want to look that up though.

You can get that from a 4", 6" or an 8" fan. I prefer the AC Infinity cloud line series, I would go with the T6 (6") fan in your case. Its always good to buy more fan than you need so that you can run it at a lower speed which usually means lower noise.

[nznene]

oh thanks very much for all that info ..
yeah i agree a slightly bigger size will be the go.

We do get a bit of humidity here year around that is either hot n humid or bloody freezing and humid !
Maybe the 8inch would be better in that case do you think ?

[MeEasy]

I just ordered a tent (I'm coming out of the closet) and just went through this and ChadWestport is correct with once/3 minutes exchange so you just take your cubic feet and divide it by 3 and that's the CFM needed... you have 2x2x2.3=9.2 c meter = 324 c feet ÷ 3 minutes = 108 CFM damn I feel like I'm in school again except I was in a serious car crash (old people pains lol) so you need a fan that will do at least that and the 4 inch I have from Ipower is like 190 something CFM which is almost double the CFM necessary and so the answer I should have given without all this bullshit, but I have OCD so I did it anyway lol is...

a 4 inch exhaust system will be fine as long as it is over 110 CFM I believe a 6 inch would give you to much negative pressure and you would probably have to add an intake fan to compensate... obviously my opinion because I am just learning about this shit too.

[nznene]

Hahahah out of the closet !
yeah good for you
Sorry to hear about all the aches and pains from that nasty accident...
I hope you recover well and soon

😊 Thanks for all your info ...

[ChadWestport]

oh thanks very much for all that info ..
yeah i agree a slightly bigger size will be the go.

We do get a bit of humidity here year around that is either hot n humid or bloody freezing and humid !
Maybe the 8inch would be better in that case do you think ?

You could, but its easier to find 6" ducting and clamps and connectors at the hardware store, at least where I'm at. I do still encourage you to get more CFM than you need because if you run them on a high setting, they can be loud. You will also lose some CFM if you have to put bends in the exhaust tube in-between the fan and the actual exit of the tent. So look for a variable speed fan and again, you can't go wrong with one of the AC Infinity cloud line series. If you listen to the grow cast with Jordan rivers on stitcher, they sponsor the show and he always has a 15% off code, just have to listen to the show, I forget it

[nznene]

ahhh yes ... after all this awesome advice i will go with a 6inch ...noise isn't too much of a problem really but i prefer the quieter grow ...
i am in New Zealand and the ease to find clamps etc at a hardware store is a real hard chore ... thank goodness we have some good growshops ... where i found pole grip fans 😁 among other handy things ..
✌

[Bootsy]

I actually do a lot of work with fans and am about to get one of the AC Cloudlines or an Iobonics in line. These have an EC motor, which is basically a DC motor - super efficient and can be turned down to 0. standard variable speed AC fans only drop to around 60% of max flow. I agree with oversizing with these ones because of the super turndown with no loss in efficiency. I do caution you if comparing flow rates of different fans/ to check the static, which is the pressure it can push. In my looking for this fan, I was surprised to find many of them were rated at atmospheric, or some other obscure wording that means it's flow was measured with no resistance. then you get it home and add ducting and the filter , which could super reduce the airflow. The AC cloudline and the iobonics are rated for their flows at a fairly high static - a very reputable way of doing it. Iobonics has a deal on for a filter , ductwork, and filter in all sizes. I wil be getting a 6 inch, even though a 4 inch will do it, in case of the future and for noise. Cheers.