lol
whats up guys/galz ?
been busy and not much on, been working on my house and grow room
and actually bump in to a mystery
that give me a bit of headache
maybe some of you guys have a wive or opinion on where I go "wrong" or miss to see ???
I`ll try to keep it short and simple
I got a 3x7x7 grow room
and a 6 inch ventilation with a filter on it
sumthing like this
View attachment 2755071
up to now I just had 3x4 inch passive intake holes with a pice of 4" ducting on each and it work fine to give me a bit of under pressure in there (the zipper door is pulled in a few inches) seems logic a 6" ventilation need about 12" of passive holes even with a filter on it
well here is the deal
I have a old 5" ventilation
like this one
View attachment 2755080
beleive the 6 ince out take ventilation is rated at 340 cfm (filter will make this less I know)
and the 5" canal ventilation is rated at 220 and 280 (two settings)
I have used the small 5" on 280 before on one of my 4" intake holes to drag in fresh air with some ducting from a open window 5-6 meters away
did notice that my zipper door did`t move more then a inch in, after that, but still some under/negative pressure
well logic as the 5" of course deliver more air and I also believe my other two 4" passive intake hole`s did`t drag much air in after fitting my 5"
now to day I wanted to make a box, to cover all my 3 passive intake holes and deliver the fresh air to the box with some new 6" ducting and my 5" canal ventilation with out the ends on (fit the ducting with out)
and what do I get a zipper door that act like a sail but now with over pressure if you like, pushing air out
had to set the 5" on 220 and even that was`t enough, had to cut a 4" hole in the end of the box (and fit some tube`s/bend`s for light proofing) to let a bit of the "fresh" air out that way
now I just have under pressure with my zipper door pulled in 1/2 a inch
Im lost, I don't expect any of you guys/galz being able to come up with a answer/solution
and its not that I need one, I think ? as my 6" outtake run as normal and I do have under pressure, Im sure I should just be happy I only need to run my 5" on low, and that I don't even need extra passive intake hole´s, actually a "relief" hole to let just a bit of fresh air out of the box or I have nighter over or under pressure
just don't make sense to me, and I keep trying to find the answer, I know its hidden in the "air being delivered to the box with the passive intake hole`s located" just don't see how I suddenly cant run it on max any more and even on low have less under presure then before, before with two passive intake holes as well ???
if I look at it in another way, it don't make sense either, how can a 5" canal ventilation that is rated at 70-80% of the 6" deliver more air on low then the 6" can handle (even with a filter on it)
guess I will have a hard time falling a sleep to night wondering what Im missing here, cant find the logic