-
in my opinion there is no need for the dimmer for the fan....from my experience there isnt a such thing as too much air flow, but there is a such thing as not enough....
In my opinion the dimmer is unnessicary especially with your setup, you can just use passive intake with some kind of filter and like kony said make sure its 3x the size of your exhaust and you shouldnt have any suction problems.
you want your fan to be pulling as much as possible the way you have your ducting setup with your carbon filter
alright talk to you some more about this in chat :D
-
Please read the entire thread before commenting.
KK:
"because if i were to close the Zipper and leave the fan on, it would start ripping my tent down the force from the fan is so strong. " & "at 440 CFM im not surprised it would take down my lttle 34 cf tent"
Sounds exactly like too much airflow to me. It's been called a tent, so I assume it's not a solid walled room. The key is 'adequate airflow' which is not always the same thing as "as much airflow as possible". With enuff suction, you could collapse a solid walled room, it's possible, but so far past adequate as to be unsuitable. So would be growing in a wind tunnel, talk about maximum airflow, lol. I also suggested passive intakes would be the way to go, but with the dimmer solution to lower CFM.
KoNY:
Please read what I typed "You are not going to slow the fans down that much to cause a 'slow hum'." Not that it wouldnt happen from going too slow, just that he wont need to slow it down to anywhere near those speeds with a speed controller. ie Dont need to worry about it. And I did suggest building his own dimmer, for the record :)
All in all, I hope I've not offered anyone crap they didnt ask for, its just my opinion, and experience, take it or leave it.
YBG
PS. I really should have started with the air calculations for basic groundwork. The air in a grow space should be exchanged approximately one time in every 3 minutes (up to once a minute in hotter climates, adjust numbers accordingly). 34cuft (your space) / 3 = base cfm 11.3cuft/minute add 5% (.565cuf) for each air cooled HID light, { or 10-15% (1.13-1.695cuf) for non air cooled lights}, add 5%(.565cuf) if you use CO2 enrichment, add 20% (2.26cuf) for an inline carbon filter on the exhaust, add 20-25%(2.26-2.825cfu) if you use 1 fan to cool the light and exhaust the space thru the light hood. If you happen to live where its real hot like southern California, add 25%, (2.825cuf) hot and humid like Florida, add up to 40%(4.52cuf). Resistance in ducting also counts, corners are bad, each 1 can further reduce the flow. Even so, you can see that the 440CFM fan is pretty beefy for the space applying these numbers.
Again, this is only 1 way to calculate the airflow needs in an indoor garden, and each space is unique and has its own variablities. Its just my opinion, and experience, take it or leave it.
YBG
-
4 Attachment(s)
Hey Guys. Little update on the Tent.
Although my fan speed adjuster hasent arrived as of yet. I made my intakes today and they are Money. I used 2 6" Elbow joint, Galvanized, and its is working great.
Tomorrow i should have my thermometer and i can do some temp tests.
For light seel, theyr pointed at the ground, and in the rear of the tent, against the wall where there is no light getting in. As well i added a double layered flap covering the zipper for light leak.
Thanks for all your suggestions guys. Heres some final pics.
Peace
