8" inline exhaust fan and carbon filter issues!

tmsculli

Well-Known Member

Aug 28, 2009

• #1

Hey guys, so i got a 500 8" fan for my exhaust and installed it at the top of my grow area. I also made one of the 3$ carbon filters that someone made in anbother thread. My problem is that with the carbon filter in there, I feel like there is not nearly enough suction or pulling power. It is a small area and 500 is plenty.

Do you think my filter is too thick? Do I have too much carbon in it?

 

S

s0high

Well-Known Member

Aug 28, 2009

• #2

What kinda of 8" fan is it. And how thick is your carbon filter bed. Retail carbon filters are like 3" of carbon or so.

 

Green Cross

Well-Known Member

Aug 28, 2009

• #3

3" is a little thick

I went 2" - with the aquarium type (fine) - and there is still a lot of resistance

 

tom__420

Well-Known Member

Aug 28, 2009

• #4

I built a carbon filter using this link: http://www.icmag.com/ic/showthread.php?p=509470

It came out great and my 306 CFM fan is fine puling through it. There is zero smell with my head in front of the exhaust exit. Here is a pic of the final product from the link

 

tmsculli

Well-Known Member

Aug 28, 2009

• #5

Oh wow that looks great tom, I may have to look into that. Problem is, I have the 8" fan, so it needs to be converted down to a size for the filter. I have the 6" to 8" converter now, so maybe I can build what you had except just use a 6" instead of a 4" piece of duct?

 

tom__420

Well-Known Member

Aug 28, 2009

• #6

If you look at the link I posted... He uses a 6 inch outer core and a 4 inch inner core. Maybe you could use an 8 inch outer core and a 6 inch inner core? That way you can still use the 6 inch ducting and the filter will be big enough for your fan

 

Q

QuentinQuark

Well-Known Member

Aug 28, 2009

• #7

What kind of fan? Axial or centrif?

 

tom__420

Well-Known Member

Aug 29, 2009

• #8

This is the fan that is use

http://www.hydroponics.net/i/133758

 

B

brucetree

Active Member

Aug 29, 2009

• #9

invest in a real carbon filter.

 

O

OrganicOzarks

Active Member

Aug 29, 2009

• #10

brucetree said:

invest in a real carbon filter.

Click to expand...

THis makes no sense as anything that is made by a person can be preplicated by another person. You can build the carbon filter like in the icmag link and it will work great.

 

TechnoMage

Well-Known Member

Aug 30, 2009

• #11

Axial fans CFM drops off real fast under load. A centrifugal fans CFM will stay steady under load, that might be the problem your having.

 

tmsculli

Well-Known Member

Sep 1, 2009

• #12

Not sure what kind it is, the box doesn't say. It is an 8" In-line duct fan that is 500cfm made by "Inductor"

Here is a link for the 6" version, they don't have the 8" on their site

http://www.homedepot.com/h_d1/N-5yc1vZ1xgy/R-100067594/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

What kind is it? I messed with the filter more and think I got it. I can't really tell until I get to time for it to smell though anyone.

 

TechnoMage

Well-Known Member

Sep 1, 2009

• #13

That's an axial fan. A centrifugal fan is going to look like http://www.plantlightinghydroponics.com/vortex-inline-fans-c-76_352.html

 

tmsculli

Well-Known Member

Sep 2, 2009

• #14

So is it most likely not going to work? Should I just keep it around until it comes to be the moment of truth and I start getting a scent? the filter I made should work, I just don't know if that fan is getting enough suction in general to do it because it is 8' in the air at the top of the closet.

 

TechnoMage

Well-Known Member

Sep 3, 2009

• #15

That's going to have to be your call as I don't know what type of risk you'd be running. I would however have plans in place at the very least. That way if you do have to switch to a new fan you'll be able to do so quickly.

tmsculli said:

So is it most likely not going to work? Should I just keep it around until it comes to be the moment of truth and I start getting a scent? the filter I made should work, I just don't know if that fan is getting enough suction in general to do it because it is 8' in the air at the top of the closet.

Click to expand...

 

tmsculli

Well-Known Member

Sep 3, 2009

• #16

That is true. I honestly just can't even tell if my set up will work. the fan is so high up. I don't really know what to do.