Carbon Filter CFM rating question

[TurboDog]

Just wondering about a 6" carbon filter thats rated at 245-425 cfm. I was lookign at a fan thats rated at 160cfm so, Im wondering if the rating on the carbon filter means you cannot or shouldnot use a fan under 245? because with teh carbon scrubber hooked up it will drop the cfms of the fan also so were talkign maybe as low as 100 cfm on the scrubber?

 

[SmilinBob]

You need to have a fan moving equal to or more cfm than what your scrubber is rating for.

The scrubber drops the cfm the fan can pull, therefore, using an already underrated fan will result in a major drop in cfm.

 

[FreezerBoy]

You need to have a fan moving equal to or more cfm than what your scrubber is rating for.

No, no. no, no, no! DANGER WILL ROBINSON! The fan rating must be equal or LESS than the filter. If the fans rating exceeds the filters, air passes unscrubbed rendering the filter useless.

 

[TurboDog]

so lets clarify this, Its ok to be under the rated cfm? is the cfm rating range on teh filters the safe limit? I don't understadn why theres a high and low rating....is one where its most affective and the other high number is the maximum before it become in effective?

 

[FreezerBoy]

If the filter is rated 245-425 cfm, get a fan that falls within that range. If the fan exceeds 425, you'll exhaust smell rather than fresh air. If not from the beginning, then far sooner than expected. My guess is that below 245, you run the risk of choking the fan, possibly causing it to overheat and burnout. It will certainly restrict air exchange heating up the cab itself.

 

[ShroomDr]

No, no. no, no, no! DANGER WILL ROBINSON! The fan rating must be equal or LESS than the filter. If the fans rating exceeds the filters, air passes unscrubbed rendering the filter useless.

So a my 75lb filter doesnt need the big loud-as-fuck fan i was sold with it?

What your saying makes sense. WTF i liked that girl that sold me that shit. She was wearing black stretch pants and kept bending over to look at the CFM ratings. I got a little distracted.

 

[stoney917]

shroom i fell for the hot hydro girl trick many a times
i run a matchin fan but run it at 1/2 speed with a controller runn full speed can cause ur filter to have a shorter lifespan. with the controller u can set it to the exact speed ya need to clean the air thus makin the fan work less hard extending the life of the fan and the filter since it will not have to clean unnessessary air flow. i run myne at half speed and never smell a thing even with the door open.

 

[Yes4Prop215]

so if my filter is this..10x39 250x1000 64 lbs 29 kilos 1400cfm 2350m3/hr 700cfm 1175m3/hr....and my fan is a 10 inch vortex pumping 800 CFM...am i good?

 

[dunkydunk]

No, no. no, no, no! DANGER WILL ROBINSON! The fan rating must be equal or LESS than the filter. If the fans rating exceeds the filters, air passes unscrubbed rendering the filter useless.

Freezerboy is dead straight with this one.

Less fan + more filter = better odor control.

 

[gloryoskie]

So let me get this right. I use a S&P 125 wired to low speed @149CFM. My box is 8 CF+/-, with (3) 4" passive intakes. Exhausting thru a filter 7" DIA x 12" length with a 4" neck, carbon bed thickness is 1.5 ", rated at 200CFM. Should I install a proper fan speed controller to decrease CFM? Lights are isolated with their own fan. First grow in this set up had zero external smell issues (Super Star, by Delta 9), but I am thinking lower air flow would be beneficial?

 

[Benjamin Check]

No, no. no, no, no! DANGER WILL ROBINSON! The fan rating must be equal or LESS than the filter. If the fans rating exceeds the filters, air passes unscrubbed rendering the filter useless.

I know I'm late but that was funny as hell.

 

[Granger2]

Yes4Prop,
No. You need a fan that pulls less than the 700 cfm your filter is rated for, or you need to speed control your fan to below 700cfm.
Good Luck. -granger