Calling all experts in the ventilation sciences...

[Hal]

I don't fully understand the ins and outs of fan technology. I will be constructing a small cabinet (34.5"h x 22.5"L x 10.5"D interior dimensions...a bit under 5 cubic feet), and want to make certain that I get enough fan to pull through a home-made carbon scrubber, and get the quietest fan that is big enough to get the job done.

Bulénath posted a real nice thread on the Panasonic whisper fan with a carbon scrubber, but the dimensions of that fan are a bit too large for my situation. I encountered another type of fan in Dr. BudGreenGenes latest thread on growing with CFL's, it is the S & P TD-Mixvent Fan, which is a mixed-flow type. This was posted by Petemoss right here:

scroll to the bottom of the page.

http://www.icmag.com/ic/showthread.php?t=88449&page=29&pp=15&highlight=fan

Here are the specs for the fan (model TD-100):

http://www.hvacquick.com/catalog_files/solerpalau_TD_Catalog.pdf

I will be running about 230 watts of CFL's (10 x 23 watts), and I want to have this fan pulling through a home-made carbon scrubber, probably 2-3" of carbon.

First question would be: does this fan have enough power to pull through that much carbon and keep the cab cool?

Then, if it will ventilate sufficiently...will it be quiet? I need this to be real quiet, real real quiet.

If so, my next question would be concerning the mounting of the fan. My thoughts now are to not have any ducting, as a matter of fact, I would like to remove the extraneous plastic on both sides of the actual fan and motor, have a carbon filter between the fan and the growchamber and have the fan exhaust straight out the top. I am hoping that the carbon between the growchamber and the fan will act as a light seal....would that be the case?

I probably have neglected to post some vital information about my plan to allow for a good answer....so, please let me know if there is anything I forgot to put down here.

Thanks for all your help!

 

[KAMy]

hey bro freezer boy is the man and answered all my questions with these 2 links let me just find them! LOL

 

[KAMy]

Try reading through these...

http://www.icmag.com/ic/showthread.php?t=89615

http://www.icmag.com/ic/showthread.php?t=29593
so adding a filter to a 300cfm fan should bring the cubic feets per minute down to about half like 150cfm thats from my experiance with a tube and a carbon anyway the smaller the can omg i dont know whats going on

 

[KAMy]

i guess the smaller carbon tube the more air flow it has ? but a homemade one hmm well make some mistakes(i would really just buy a filter) but thats what lifes about learning from your XP! good luck ill ready try helpin ya out tomorow or something when i feel awake

 

[KAMy]

i really like the idea of using a 4 inch elcent in a beer cooler with some kushie pads under it that was my idea a while ago but i also saw it in a pic on icmag somewhere geez i hope im not spamming lol

 

[petemoss]

Howdy Hal,
That TD-100 is a great little fan. I hooked it up briefly to test and it runs smooth and quiet. The fan itself is very quiet, no vibrations. The only sound is the Whooosh of air exiting. That could be quieted with insulated ducting or a duct muffler or with the scrubber at the exit end. I can slow down the fan with a two-wire control without hum. In fact, it doesn't need to be slowed down. There's a hi and low setting you hard wire. I had it hooked up to suck through a small "Elf" filter and then pushing air through a cooltube and out the back of my cab. I didn't want to try running the fan at the exit end sucking air out because a sticker on the fan warns not to use with temps above 104 deg F. If I had it After the cooltube, the hot air may cause the thermal shutoff to kick in and shut down the fan with disasterous results.

 

[Bumble Buddy]

Hal, I think that any fan with sufficient pull through the static pressure of a carbon filter (unless the filter is very small, and you used a computer case fan or similar very small vent fan, i.e. a commercially available quiet personal air filter) would likely cause more noise than you would find acceptable. A 4" inline fan or 4" Panasonic inline (which is actually a scirocco fan) can be quieted significantly by insulating the fan body / ductwork and adding a muffler for the outlet whoosh. There are a couple good threads on making a DIY muffler, Fantech and others sell mufflers as well. If you take a look at the static pressure chart of those mixvent fans, they seem to be less capable of pulling/pushing than a comprable inline; there is a similar chart on the Fantech website for their FX4 inline that you could compare with. It is possible that the mixvent would be better for you than a centrifugal inline though, tough call without direct comparison due to so many variables: my guess is that you will need to do significant modifications to quiet the noise either way.

 

[Hal]

Thanks fellas....

I'm actually considering going with an entirely different design, one that would negate the need for a fan with the power of those mentioned above.

This will need to be experimented with, but I have a feeling that I can eliminate the carbon scrubber altogether, and instead use the scented disks that go with the vaportronic system. The neutral scent disks are supposedly the only ones that can delete the odor of cannabis.

The plan is to put one of these discs into the screen covering the passive intake at the bottom of the cabinet. I should be able to use a much less powerful fan because there won't be nearly the resistance that the carbon scrubber will present.

Will it work? Won't know until I try...but it is worth a shot.

 

[Bumble Buddy]

I think that REZDOG suggested doing something like that with the Vaportronic discs and a computer case fan, might want to search his posts...