CFM backpressure

[YASoob]

i was reading this on another thread fans are tested without ducting which give them the cfm. The thread also mention that if you use ducting, it will cut the cfm by half. No one on that thread asked if it will cut more than half if ducting and carbon filter is use.
It got me thinking since i just upgraded and i need a fan that will cool 2000watt in a 64 cubic feet room. Any input on this would be great. thanks in advance

YASoob Reviewed by YASoob on 11-28-2006. CFM backpressure i was reading this on another thread fans are tested without ducting which give them the cfm. The thread also mention that if you use ducting, it will cut the cfm by half. No one on that thread asked if it will cut more than half if ducting and carbon filter is use. It got me thinking since i just upgraded and i need a fan that will cool 2000watt in a 64 cubic feet room. Any input on this would be great. thanks in advance Rating: 5

[JackdaWack]

http://boards.cannabis.com/showthread.php?t=91905

But either way if your going to be using a carbon filter get an inline vortex or something, the blowers are week on static pressure. they dont lose much when using venting but they do on the filters

[harris7]

The way they test fans is the same way they test any consumer product.
Under the conditions that will allow it to perform best.

It is a fair basis for comparison. As well flow is reduced when ever you do anything. If you bend the tube at 90 degrees: flow reduces by 60%

There are ways to keep for flow up, big ducts help a lot. It’s an exponential curve. 8inch is Way probably twice as good as 6”

[xcrispi]

hey yasoob ,
gimme some more input . cooltubes ? air-cooled hoods ?
i'm running 2 - 1000w. hps. inline in cooltubes w/ a pair of 630 cfm. hurricanes . 1 pushin , 1 pullin through the cooltubes which is probably way overkill but i have a cpl. sharp bends . i also run a fan speed controller and slow them down some . my 10 x 12 room is 72 degrees -n- you can lay your hands on the cooltubes for extended periods of time w/ fear of ever being burned . also only use as much of the flixable dryer duct as you absoultely have to , it reduces airflow drasticly . use metal galvanised stove pipe .
peace
crispi

[YASoob]

hey yasoob ,
gimme some more input . cooltubes ? air-cooled hoods ?
i'm running 2 - 1000w. hps. inline in cooltubes w/ a pair of 630 cfm. hurricanes . 1 pushin , 1 pullin through the cooltubes which is probably way overkill but i have a cpl. sharp bends . i also run a fan speed controller and slow them down some . my 10 x 12 room is 72 degrees -n- you can lay your hands on the cooltubes for extended periods of time w/ fear of ever being burned . also only use as much of the flixable dryer duct as you absoultely have to , it reduces airflow drasticly . use metal galvanised stove pipe .
peace
crispi

cooltube 2k watt. i didn't upgrade the fan part yet. but yes, i'm getting a vortex brand for sure. I just wanted to check the cfm rate i need to cool 2k watt. I have to initial setup in mind.

1.) suck air in carbon filter-> 8" vortex -> 2k watt -> out the window

2.) suck air in carbon fitler -> 6" vortex -> out the window
suck room cool air -> 6" vortex -> 2k watt -> out the window

no point in burning money if i only need a 8"vortex to cool 2k watt instead of duel 6" vortex. Crispi, How loud does it get in your room with 3 fan ? oh and damn that one scary looking dog.
what is this cpl sharp bend? and doesn't the metal stove pipe have small hole for light leaks?

[YASoob]

so what u guys think? one 8" vortex or duel 6" vortex?

[doco]

2.) suck air in carbon fitler -> 6" vortex -> out the window
suck room cool air -> 6" vortex -> 2k watt -> out the window

I'd go with plan 2.) but use an 8" for the cooltubes. I use a 6" for a 400w and it could cool two but for 2 1000w I'd feel a little better with a bigger one. If you dont need all the power or want to quiet it down some, get one of those speed controllers for fans.

At one time I considered doing what you planned in 1.) but several of the people here thought it was not a good idea to draw through the carbon filter first, then over the lights so I ended up with two fans.

[YASoob]

2.) suck air in carbon fitler -> 6" vortex -> out the window
suck room cool air -> 6" vortex -> 2k watt -> out the window

I'd go with plan 2.) but use an 8" for the cooltubes. I use a 6" for a 400w and it could cool two but for 2 1000w I'd feel a little better with a bigger one. If you dont need all the power or want to quiet it down some, get one of those speed controllers for fans.

At one time I considered doing what you planned in 1.) but several of the people here thought it was not a good idea to draw through the carbon filter first, then over the lights so I ended up with two fans.

would u happen to know how much percent will be lost from if pulling from the carbon filter to the vortex?

anyone else concur or differ?

[doco]

BTW, I intend that air for the cooltube would be drawn in from outside the grow area so as not to need deodorizing. Here's how mine is setup: http://boards.cannabis.com/showthrea...t=88985&page=2

Much smaller area than yours of course my same principals apply. In my pictures the carbon scrubber gets attached to the Dayton fan in the top corner.

[YASoob]

is your cool air comming from your bathroom or the hallway of your house?

I wanted to try 1.) do to the fact that it has lower expenses. Also, i converted my closet, so i only have 1 side to work with.

2.) a good way to control condition, but with more expenses. Oh And also i can't cut holes in my apt.


Im still trying to find more information on method 1.) because not much ppl do it this way with good sucess. 2.) works will work well. I just trying to compare both methods.