which design would you go with?

[gualapa]

I got two different designs here for my ventilation system:

the second design has no small fan below the lights so that both of the takeoffs get fresh air from the intake. dampers & 2 ft past takeoff are supposed to make airflow smoother + allow fan not to starve. I'm still contemplating which one to go with though

 

[pip313]

Top, heat rises so you only need 1 inlet for the exhaust fan but the fan under the bulbs helps the plants from burning.

 

[willyweed]

have a look at the pics in the vert section,they put the filter over the light and the fan under,you are not trying to reinvent the wheel,go with what has been proven to work well

 

[gualapa]

yeah I've chosen to go with the first one. one last thing- I aws trying to find how to choose the right carbon filter, but haven't found anything yet. I'm sure it has to match up for the fan I'm going with. Would I get a carbon filter that has the same diameter (10") & cfm rating as fan (790 cfm)?

 

[Sour Seed]

your just after a cfm rating- and if you go with the first one id go with the same size scrubber diameter as my fan- but def look into the carbon filters handling cfm rating- thats really the most important thing when choosing a filter to match your fan-

 

[frankenstein2]

How big is your intake of fresh air? If your using a 10" exhaust fan your intake should be at least that size, preferably twice the size of the exhaust with passive intake. I would have two ten inch passive fresh air inlets. I have a room that size now(my current grow ended, and now im back at the old spot,shhhhhh, no one's suppossed to know yet) Back to the topic. I have three fans sucking air out, the 400+ cfm fan's. No fresh air for me, co2 and ac. My ac is grossly undersized for 3 1k's, only 10,000 btu's. What i'm getting at is i like to have a fan for each light, without it, in my limited situation the room would be in the 100's. Don't forget when using long ductwork and filters the cfm's of the fans are greatly reduced. The numbers they say the fans move are with the fan running bare with no attachments. There is no overkill when it comes to air movement in the room. Even with fans pulling filtered air out of the room constantly, my co2 burner rarely comes on and a 20 lb. tank usually last a month. Sorry for the rant i get excited. So yes ten inch scrubber to go with ten inch fan for sure. I would have two if i was you.

 

[gualapa]

ok, but does the cfm rating of the scrubber need to be equal to the cfm rating of the fan, or higher?


Frankenstein, for my passive intake hole, I used the formula from the Vent 101 thread: A = pi * (radius)^2 -> A = 3.14*(5^2) = 78.5 X 2 = 157

sqrt(157) = 12.5" X 12.5" square intake hole. anymore intake holes I'll have more 2 X exhaust which creates losses. also, if I went for multiple fans in my design again I'd have to change the specs entirely because I don't want to replace the air more than once per minute and at 790 cfm in a 1140 cf room, I'm replacing the air less than every 2 minutes already.

Also, I'm going to try and use hard piping instead of flex to make the system more efficient. The piping in the room itself won't be more than a few feet, and I'm going to use two 45 degree angles

 

[greenmatter]

how are you going to hook ducting to the outside of the scrubber anyway?

you need to read the ratings on the filter. they will be different for single pass and scrubbing

 

[Sour Seed]

yup^^

 

[FlowerFarmer]

What brand of 10" inline scrubber are you planning on using?
I wasn't aware they made inline scrubbers this big.



Why over complicate things with the ductwork? Why not just hang a traditional filter from the ceiling and evacuate the hot air as it rises.
It is not like the hot air rising from the bulb is going to make it's way back down to the plants. (provided the small fan under the lamp is not too powerful).


I'd just do photo #1, with a traditional filter instead of the inline and eliminate all that other stuff. Filter > Fan > Out. The duct-work is entirely unnecessary and will only lead to reduced flow.

Similar to this. There is 5000w in this room. Heat is not an issue so long as passive intake temps remain reasonable.

 

[gualapa]

that makes sense. I'll just eliminate the duct work. The duct work wasn't gonna be very long in the first place. I'm probably going to go down to 8".

I have no idea what scrubber I'll be using, that's why I'm asking how to choose the correct one. obviously the flange needs to be 8" as well, but what should I be looking for in terms of cfm rating for a carbon filter? (does this rating need to be higher than the cfm rating of my fan or equal?)


updated blueprint:

(the 45° angle is there because I need to go out of the ceiling, I figure two 2 45°'s are better than using two 90's in my case)

 

[greenmatter]

look at the numbers for recirculation and exhaust in the specs for different filters and match your room and fan to it

it's the first two sets of numbers in the specs here ......http://canfilters.com/canfilters_100.html


remember that the fan ratings are with no load ...... a 740 cfm fan with not pull 740 cfm through a carbon filter

 

[gualapa]

I purchased this fan, got a really good deal on it (10", 589 cfm): http://www.grainger.com/Grainger/FA...H-Inline-Centrifugal-Duct-Fan-4YM41&Pid=searc

Not as high cfm as I originally planned but I did the math, even when at it's lowest cfm rating (355 cfm, due to 90 degree angles or carbon filter slowing it down, I doubt it'll go that low), my room should still be replenished with fresh air every 3 minutes.

Now for the carbon filter, I understand I need to match the cfm rating. Is it okay if the filter has a higher cfm rating than my fan does? I've taken a look at can, rhino, phresh, mountain air, & phat filters, but not many 10" have a low cfm rating. Would this phat filter do? It's 10" 700 CFM (my fan is 590 cfm but will run lower than that obviously): http://www.horticulturesource.com/environmental-controllers-co2-generators-fans-blowers-duct-ducting-air-purification-c43/air-filters-purification-carbon-filters-odor-control-bug-nets-etc--s42/phat-filters-24-x-10-700-cfm-p11553

 

[FlowerFarmer]

You want the numbers to be roughly the same.

Too large a fan on a filter and you'll pull air over the carbon too quickly - possibly resulting in odor escaping by.

If ya got the budget....
this may be overkill, but I'd go with a MAX 10" (1000CFM) paired with a Can Filter 100 or 150. Just because the MAX 10 is a little powerhouse and very quiet.

I'd stay away from the MAX 8 (plastic - cannot speed control), but Can has recently released a new MAX 8 HO, which is a MAX 10 in a 8" body. This new model has a speed control built into.



or.. go with the 747CFM 8" Vortex paired with a Can Filter 100.


EDIT - didnt see your previous post before posting. Yes - OK if the filter is a hair over spec then the fan. Too small a filter could result in not enough contact time with the carbon, but slightly over spec is a'ok.

 

[gualapa]

alright thank you. I really wanted to go with a bigger fan, but 590 cfm vs 747 cfm isn't that much difference (150 cfm less) and I got a great deal on the 10" 590 cfm fantech.

I'll take a few pics once I'm done setting it all up, room's coming together real good.

 

[lordofthenugz]

I know you already decided in favor of fan below and I would just like to add in a comfirmation. I run 2kw stacked vert coco dtw, you are gonna need that fan below. I use a box fan on top of a crate. W 2kw the small fans seemed a but anemic. Also, always over spec on filter compared to fan, never under spec.

Peace!

 

[Jamorg13]

Get a max fan. Vortex are way overpriced for there performance. I think the 12 inch max fans are basically king of the inline fan world, that's all I buy. They are priced great, and move a SHIT TON of air.

 

[Jamorg13]

And design 1 is the best IMO.