Grow Room Quietest in-line fan?

[Sage]

I'm confused on this a little bit. Does the fan not have to be running at the proper cmf rated speed for the filter? I was under the impression that if you had a filter rated to be used at 400cmf it needed to be around 400cmf for it to work properly. I thought the only thing the speed dials might be good for would be so you could use the same fan on different size filters. I'd love to hear your opinions on this. Thanks!

Dunno...works for me and I've not only got it pulling through the carbon filter in the tent there's an inline carbon filter on the end of the ducting as well. Sure it's not 'correct' but it works for me, the air coming out doesn't smell at all, super steathly :smoking:

 

[Simplicio]

It's likely that almost any fan speed above 20% or so can make good use of a carbon filter.
As long as there's any exhaust air flow at all, it had to go thru carbon.
I've run an old fashioned inline fan at about half the "L" speed (that I'd estimate to be about 10% of full speed) without smell.

 

[Weescar]

I'm confused on this a little bit. Does the fan not have to be running at the proper cmf rated speed for the filter? I was under the impression that if you had a filter rated to be used at 400cmf it needed to be around 400cmf for it to work properly. I thought the only thing the speed dials might be good for would be so you could use the same fan on different size filters. I'd love to hear your opinions on this. Thanks!

The way I understand it, which could possibly be wrong....
The filter would be MAX rated at 400 cfm, you can run it under if you want, run it over the stated cfm it will not work as well as the amount of carbon in the filter won't scrub the air properly. I normally run a filter and ducting a size up from my fan, which is already oversized for the size of room and run it on a fan controller at lower speeds. It reduces noise a lot, and future proofs it for dealing with winter and summer temp variations. I currently vent into my sitting room, carbon filter is placed outside the tent, after the fan, downstream I guess you could call it.


Here is what it looks like inside a carbon filter, some have crushed carbon, some have pellets, the air simply passes through this wall of carbon being scrubbed as it goes.

 

[wes]

I’m using a 4” vivosun fan in my 3x3 vivosun tent. It’s very quiet inline between the filter and exhaust tubing. 100cfm and under $20 shipped.

 

[McDee]

The way I understand it, which could possibly be wrong....
The filter would be MAX rated at 400 cfm, you can run it under if you want, run it over the stated cfm it will not work as well as the amount of carbon in the filter won't scrub the air properly. I normally run a filter and ducting a size up from my fan, which is already oversized for the size of room and run it on a fan controller at lower speeds. It reduces noise a lot, and future proofs it for dealing with winter and summer temp variations. I currently vent into my sitting room, carbon filter is placed outside the tent, after the fan, downstream I guess you could call it.


Here is what it looks like inside a carbon filter, some have crushed carbon, some have pellets, the air simply passes through this wall of carbon being scrubbed as it goes.
View attachment 960841 View attachment 960842

You are correct. 400 would be max cfm's for that filter. The slower air passes over the carbon, the better it is filtered. The same goes for water, the longer it's in contact with the carbon the better it works. That's why brita filters are not good lol.