S&P, which fan?

[StealthyScrog]

for a 420 watt cab, in an extremely small area, 6"x57.5"x28" length x width x height, with supplement lights placed in every available space for max production in a small space, but what should i ventilate with? would a td-125 be able to handle this and a durban poison carbon filter in this cab with lights?

 

[hempknowsis]

Do you mean 60" or 6"?

 

[BioMechanical]

How to size your exhaust fan
There are many calculations on the web for sizing a fan for ventilating grow rooms; however, what these calculations fail to take into consideration is the friction loss on carbon filters, increased temperatures from HID lights and CO2, etc. The following calculation can be used as a guide for sizing an exhaust fan for a growing area (keep in mind that this calculation will give you the lowest required CFM required to ventilate the grow room):

Step 1 – Room Volume
First the volume of the room needs to be calculated. To calculate multiply length x width x height of growing area e.g. A room that is 8' x 8' x 8' will have a volume of 512 cubic feet.

Step 2 – CFM Required
The fan should be able to adequately exchange the air in a grow room once every three minutes. Therefore, 512 cubic feet/3 minutes = 171 cfm. This will be the absolute minimum cfm for exchanging the air in a grow room.

Step 3 – Additional factors
Unfortunately, the minimum cfm needed to ventilate a grow room is never quite that simple. Once the grower has calculated the minimum cfm required for their grow room the following additional factors need to be considered:

1. Number of HID lights – add 5% per air cooled light or 10-15% per non-air cooled light.
2. CO2 – add 5% for rooms with CO2 enrichment
3. Filters – if a carbon filter is to be used with the exhaust system then add 20%
4. Ambient temperature – for hot climates (such as Southern California) add 25%, for hot and humid climates (such as Florida) add up to 40%.

 

[FreezerBoy]

The S&P just doesn't suck like a centrifugal. Consider getting the model one step up from what you "need."

 

[qbert]

for a 420 watt cab, in an extremely small area, 6"x57.5"x28" length x width x height, with supplement lights placed in every available space for max production in a small space, but what should i ventilate with? would a td-125 be able to handle this and a durban poison carbon filter in this cab with lights?

I bought a td-200 (8") to exhaust a 3'x2'x6' cab (400w hps) through a Can-Filter 33. (and that's with a td-150 pushing through the hood separately) The fan is probably two sizes above what I need, but I wanted to go with the 8" ducting and be sure I had enough flow.

I would think the td-125 will be on the small side for you, assuming that's not really supposed to be 6" in your cab measurements.

 

[StealthyScrog]

Do you mean 60" or 6"?

6 " its the space im working with, and its gonna be a sog style

How to size your exhaust fan
There are many calculations on the web for sizing a fan for ventilating grow rooms; however, what these calculations fail to take into consideration is the friction loss on carbon filters, increased temperatures from HID lights and CO2, etc. The following calculation can be used as a guide for sizing an exhaust fan for a growing area (keep in mind that this calculation will give you the lowest required CFM required to ventilate the grow room):

Step 1 – Room Volume
First the volume of the room needs to be calculated. To calculate multiply length x width x height of growing area e.g. A room that is 8' x 8' x 8' will have a volume of 512 cubic feet.

Step 2 – CFM Required
The fan should be able to adequately exchange the air in a grow room once every three minutes. Therefore, 512 cubic feet/3 minutes = 171 cfm. This will be the absolute minimum cfm for exchanging the air in a grow room.

Step 3 – Additional factors
Unfortunately, the minimum cfm needed to ventilate a grow room is never quite that simple. Once the grower has calculated the minimum cfm required for their grow room the following additional factors need to be considered:

1. Number of HID lights – add 5% per air cooled light or 10-15% per non-air cooled light.
2. CO2 – add 5% for rooms with CO2 enrichment
3. Filters – if a carbon filter is to be used with the exhaust system then add 20%
4. Ambient temperature – for hot climates (such as Southern California) add 25%, for hot and humid climates (such as Florida) add up to 40%.

i got under 10 cfm using this formula! and thats with carbon filter 25% hot climate, i practically live about an hour from the border of the canadians) and all that stuff

The S&P just doesn't suck like a centrifugal. Consider getting the model one step up from what you "need."

according to your chart, id want a 5-10 ambient, putting me roughly at 125-250, and im sure thats for hid, which is not much hotter then cfl, but the td125 is For 5 inch round duct - 197/149 cfm (high/low), and im sure a filter would drop me 75 cfm for a carbon filter, the td-150 6 inch would put me at 300 cfm on high, with a filter probably 220-250 cfm, enough to put me at 5 degrees ambient, am i right in my thinking freezerboy?

I bought a td-200 (8") to exhaust a 3'x2'x6' cab (400w hps) through a Can-Filter 33. (and that's with a td-150 pushing through the hood separately) The fan is probably two sizes above what I need, but I wanted to go with the 8" ducting and be sure I had enough flow.

I would think the td-125 will be on the small side for you, assuming that's not really supposed to be 6" in your cab measurements.

well my cab is 5.6 cubic feet total (suprising) and yours is 36, thats a 36% increase on fan flow , same lighting (although hid) and 15% increased cab space, two sizes down from td 200 is the td125 anyways

 

[StealthyScrog]

haiiiiii

 

[Mafutero]

would a 34.5cfm(12v) fan with a 4.9v output 13.8 or 7.04cfm? or is this a stupid question?