Help with exhaust fan selection

CapnBligh

Member
Hello everybody! I need some help with an inline fan selection. Room is roughly 4'x8' (1.2m x 2.4m for my metric friends) and I am in way over my head. Phresh filter is telling me I need a 400 cfm filter, totally cool with that part. It is picking out the fan that sends my head swirling.

I am looking for something that is rock solid and has a controller that works properly. I can wire up a controller if it isn't a major undertaking, but this project has enough shit going on. Any reccomendations? Cost effective is always a plus, but if dropping some coin is worth it I am up for it. I am going to run the Phresh filter if that matters. Wife says no "god damn pot factory smell"
 
Since AC infinity are axial fans, I'd consider the 8" version since you are planning on using a Phresh. More power at lower settings and thus quieter, plus if you need the extra power it's there.
Should I upsize the filter as well if I go that route?
 
If your room is 8' high, you only have a volume of 256 cubic feet. A good 4" fan is 150-200cfm. Thats plenty for your space. You could use the filter mentioned but you dont need a 8" fan, thats just ridiculous.
 
If your room is 8' high, you only have a volume of 256 cubic feet. A good 4" fan is 150-200cfm. Thats plenty for your space. You could use the filter mentioned but you dont need a 8" fan, thats just ridiculous.
Yeah, it is 8' high. Probably should have thrown that info in there.
 
Flower portion is roughly 4x4x8 with a diy LED. Should be about 500w at full power based on spec sheets. Will have at least (1) 2x2x4 for veg and clones. Roughly 90w for those. I have a light I built for an aquarium that didn't make the latest move I am using for veg right now. 27 3w diodes in a big tool chest. I picked those up from mouser and digi key, they are legit CREE XPG3 diodes. 6500k and 4000k mixed. Did a great job growing plants in the aquarium. I had some anubis flowering underwater lol.

I don't think heat will be an issue, it rarely gets over 85 in the sun during summer. Teens and single digits during the winter.

Edit: I mean to say, not the biggest concern. I am more concerned about turnover rate for fresh air. I see stuff all over the spectrum as far as how much you should have. Once per minute up to once per 5 minutes and the it's all over the place. Not planning on running co2 ever.
 
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Flower portion is roughly 4x4x8 with a diy LED. Should be about 500w at full power based on spec sheets. Will have at least (1) 2x2x4 for veg and clones. Roughly 90w for those. I have a light I built for an aquarium that didn't make the latest move I am using for veg right now. 27 3w diodes in a big tool chest. I picked those up from mouser and digi key, they are legit CREE XPG3 diodes. 6500k and 4000k mixed. Did a great job growing plants in the aquarium. I had some anubis flowering underwater lol.

I don't think heat will be an issue, it rarely gets over 85 in the sun during summer. Teens and single digits during the winter.

Edit: I mean to say, not the biggest concern. I am more concerned about turnover rate for fresh air. I see stuff all over the spectrum as far as how much you should have. Once per minute up to once per 5 minutes and the it's all over the place. Not planning on running co2 ever.
The 4" is fine for turnover but might not be enough to keeps temps down during peak summer...in that case a 6" with a speed control is all you need
 
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