Fastest 4" Inline Fan?

H_Aspect

H_Aspect

Active Member
I have a 190 CFM inline fan connected to a 4x12" 204CFM filter with a muffler on the other end. Is there a faster than 190 CFM 4"? Here is my setup:

<--- [MUFFLER]=[FAN]=[FILTER]<---Air Direction

For some reason I can't really feel any air being sucked out of the filter. Maybe it's working, maybe not, but it's certainly not reducing temps. Before I had the filter installed temps were 75. After the filter they are minimum 81+. I solved that easy by attaching an A/C unit to my setup pushing 72 degree air in, which keeps the temp at 73 in one corner and 75 in the other.

HOWEVER, it's puffing the tent out like the Stay Puft Marshmallow Man. My (limited) understanding is that when it starts to flower the A/C unit will be pushing the odor out all available holes in the tent. If I turn the A/C unit fan down to low, the temps hover under 80 (78-79).

1) Is there a faster 4" fan?
1a) Would that help?
2) Is this positive pressure going to stink things to high hell, like I suspect?
3) Is 78-79 fine and just deal with it?

Sorry for the long post. Note, I have a 6" fan but didn't think I'd need it for this setup, so I bought a new filter and new muffler - first time using them and I need to minimize noise. This would require me to redo all the ducting and buy a 6" filter to go that route.
 
Banana444

Banana444

Well-Known Member
H_Aspect said:
I have a 190 CFM inline fan connected to a 4x12" 204CFM filter with a muffler on the other end. Is there a faster than 190 CFM 4"? Here is my setup:

<--- [MUFFLER]=[FAN]=[FILTER]<---Air Direction

For some reason I can't really feel any air being sucked out of the filter. Maybe it's working, maybe not, but it's certainly not reducing temps. Before I had the filter installed temps were 75. After the filter they are minimum 81+. I solved that easy by attaching an A/C unit to my setup pushing 72 degree air in, which keeps the temp at 73 in one corner and 75 in the other.

HOWEVER, it's puffing the tent out like the Stay Puft Marshmallow Man. My (limited) understanding is that when it starts to flower the A/C unit will be pushing the odor out all available holes in the tent. If I turn the A/C unit fan down to low, the temps hover under 80 (78-79).

1) Is there a faster 4" fan?
1a) Would that help?
2) Is this positive pressure going to stink things to high hell, like I suspect?
3) Is 78-79 fine and just deal with it?

Sorry for the long post. Note, I have a 6" fan but didn't think I'd need it for this setup, so I bought a new filter and new muffler - first time using them and I need to minimize noise. This would require me to redo all the ducting and buy a 6" filter to go that route.
Click to expand...
1) not sure about 4" fans, they are not real common, its not one of those booster fans is it? Those things dont move hardly any air and wont work with a carbon filter.
2)only one way to find out
3)those temps should be ok as long as you have good airflow and you have a temp drop when lights are off.

What kind of fan is it?
Whats the filter cfm rated for?
If you dont feel the fan moving any air, its likely not moving any air.
You could still use the 4" filter with a 6" fan, you just need a 4"-6" duct reducer, but you will lose some cfms, but shouldnt be a major issue.
 
H_Aspect

H_Aspect

Active Member
Thanks Banana,

It's a 190cfm 4" fan - it's a legit inline fan, not a booster. Fan is rated for 190cfm, filter is 204cfm. Fan is pushing through a muffler, then through 20~feet of ducting. The 6" fan looks identical (padding, etc) and is 440 cfm. I assume it would destroy that filter with a quickness. The tent is only 10sq/ft of lit area & 40sq/ft in total area (its a 2x4x5 tent).

Guess what? I just stuck a receipt to the bottom and it fell off!! But when it got near the top it sucked it like a $3 prostitute. Weird, the bottom doesn't seem to be working. But hot air rises, right, so I guess all is good?

It's White Widow Auto, so lights are on 24/7. Plants are 8/9 days old and looking fine. I have an A/C unit connected, so based on what I set the temp as I can control the grow area temp to whatever I want. One corner was 73 low 75 high today and the other corner was 77/79. But that thermometer is much closer to the light, and much closer than the plant.

I guess I'm just going to roll with it and if smell becomes an issue buy a 6" filter and a reducer to keep the muffler. At least then I can keep all the 4" ducting, too.
 
Coloradoclear

Coloradoclear

Well-Known Member
I run the exact 4" setup, phresh filter, 170 cfm hurricane fan, duct muffler, blowing out a dryer vent lol. So what you have is a leak in your piping most likely. At 190 cfm should be able to hear the air being sucked into your filter. My line is: filter, ductwork, fan, muffler , duct, exhaust.
 
H_Aspect

H_Aspect

Active Member
Coloradoclear said:
I run the exact 4" setup, phresh filter, 170 cfm hurricane fan, duct muffler, blowing out a dryer vent lol. So what you have is a leak in your piping most likely. At 190 cfm should be able to hear the air being sucked into your filter. My line is: filter, ductwork, fan, muffler , duct, exhaust.
Click to expand...
I considered that... damn. Here is my setup: Filter to flexible duct hose out the tent to the fan (2' maybe). Fan directly on top of muffler. Duct hose from muffler to exit, 15-20~, I didn't measure.

In theory I can vent out to the room only and just use the A/C exhaust (already out the window). I tried to upload pics and it just says "Error" for some reason.
 
Banana444

Banana444

Well-Known Member
H_Aspect said:
I considered that... damn. Here is my setup: Filter to flexible duct hose out the tent to the fan (2' maybe). Fan directly on top of muffler. Duct hose from muffler to exit, 15-20~, I didn't measure.

In theory I can vent out to the room only and just use the A/C exhaust (already out the window). I tried to upload pics and it just says "Error" for some reason.
Click to expand...
If you disconnect the fan from everything and turn it on, does it move air? Can you connect your 6" fan to the filter and see if that moves air? Maybe its a clogged/bad filter. I have never had that problem but just trying to break it down peice by peice and find the problem. Is the fan backwards blowing into the tent?
 
H_Aspect

H_Aspect

Active Member
Banana444 said:
If you disconnect the fan from everything and turn it on, does it move air? Can you connect your 6" fan to the filter and see if that moves air? Maybe its a clogged/bad filter. I have never had that problem but just trying to break it down peice by peice and find the problem. Is the fan backwards blowing into the tent?
Click to expand...
Yeah, I appreciate all the help, for sure. Sometimes it's right in front of your face and you never notice, so thanks for helping me troubleshoot.

Yeah, the fan is moving air for sure, and in the correct direction. I had everything set up before the filter arrived so I just used it as-is for a few days without the filter and it was definitely sucking air out. After connecting the filter I can barely feel anything at the bottom. Like I said, apparently the top is working. The receipt stuck to it right away. But why not the bottom?? Life shouldn't be this weird.

It's an iPower 4"x12" filter from eBay, but I used an 8" just like it for the last grow and it worked great. I couldn't find the 8" any longer and I saw this and thought - 4 more inches!! I didn't want to reuse the old one so I thought I'd get this one. I guess I'll just switch to the 6" before flower. I use an Ona Bucket and Ona Breeze during flower and that thing works magic.
 
H_Aspect

H_Aspect

Active Member
@Banana444 @Coloradoclear

Yeah, let me just switch to the 6". That's probably WAY too over powered for a 4x2x5 tent (length x width x height) but I see a few different deals online I'd like your input on.

1) Carbon Ace Carbon Filter 6x23 550 cfm - $36.69
2) Black Ops Carbon Filter 6x16 400 cfm - $31.71

My 6" fan is 440 cfm. I actually think I have a 6" to 4" reducer here somewhere so I wouldn't need to change all the ducting I did.

Thoughts?
 
Banana444

Banana444

Well-Known Member
H_Aspect said:
@Banana444 @Coloradoclear

Yeah, let me just switch to the 6". That's probably WAY too over powered for a 4x2x5 tent (length x width x height) but I see a few different deals online I'd like your input on.

1) Carbon Ace Carbon Filter 6x23 550 cfm - $36.69
2) Black Ops Carbon Filter 6x16 400 cfm - $31.71

My 6" fan is 440 cfm. I actually think I have a 6" to 4" reducer here somewhere so I wouldn't need to change all the ducting I did.

Thoughts?
Click to expand...
Sounds like a good deal, but i dont have any experience with those filters. I dont skimp on odor control, phresh filters all the way, i get a new one about every 12 months but they are good for about 16+ months if you keep your humidity in check, if you didnt know high humidity drastically reduces the life of carbon filters.
 
H_Aspect

H_Aspect

Active Member
Banana444 said:
Sounds like a good deal, but i dont have any experience with those filters. I dont skimp on odor control, phresh filters all the way, i get a new one about every 12 months but they are good for about 16+ months if you keep your humidity in check, if you didnt know high humidity drastically reduces the life of carbon filters.
Click to expand...
I keep seeing people recommend them. I had actually seen them on Amazon and just went back to see why I didn't consider it. The 4"x12" Phresh Filter is 200 CFM, costs $77, and has 3.9/5 stars. I think it was price and reviews that made me consider others.

I figured a workaround though. I cut the duct much shorter. What I did was leave it filter-fan-muffler, but cut the ducting off the muffler down to about 6' from the 20-25 it was and let it vent back into the room. It's blowing into kind of a box thingy with the Ona pail in it. The room itself is a constant 73, and it smells fantastic now. 8)
 
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