help ventilating a 4.5' x 8' tent

[blooper]

i'm upgrading my inline fan which will be used to cool at least 1000w if not 2 600w HIDs and will likely either be going with 710CFM hyper fan stealth by phresh or the 932CFM max-fan with 3 speed setting ranging from 749CFM, 849CFM, 932CFM. whichever i choose will be installed in a foam-padded box and connected to a duct silencer in hopes i will no longer be bothering my family. generally i run a 6" inline fan to scrub and cool the hoods as well as a portable A/C to help out the fan when necessary. not a sealed room so probably not the most efficient.

some of my concerns are whether or not the upgrade to an 8" fan is overkill considering the size of the tent and how much ducting will cut down on the efficiency of the fan. i don't see any way around at least 10'-20' of ducting before it will be vented outside which is why i'm considering over twice my usual rate of airflow.

another concern is not using an air conditioner. i need to cut down on noise as much as possible so unless absolutely necessary, i would prefer to scrub and exhaust the room with a single 8" fan. it will be hot here this summer but the area of the house i grow in is usually about 70f tops so i figure with enough air exchange, mid 70s to 80s shouldn't be too hard to achieve.

only other configuration i can think of is a loop of outside air for the lights, a fan with a scrubber running inside the tent at all times, and the portable A/C as a sealed system rather than using exhaust fans.

any experience or input on this type of thing? seems most people either recommend a sealed tent with A/C or just run a single fan to scrub and exhaust the heat from the lights. my main concern is noise and electricity usage. the only reason i'm re-doing things is because of complaints over pumps/fans. any help is appreciated!

 

[_tessarecting]

You can put a dimmer on the inline if its overkill for noise and climate control.

 

[Epiphyte]

A larger fan with a dimmer is always the best option. Where is your intake coming from. Sometimes even if you move more air the temp will stay the sameish.

 

[blooper]

thanks!

i've had problems with fans making a loud humming sound when reducing speed using a speedster fan controller. the fan running full blast is almost preferable to the ear-piercing frequency it hums at when turned down. i've read variac speed controllers don't have this problem but i've heard conflicting reports which is why i'm looking into a fan that already has 3 speeds built in.

the intake is passive just bringing air from the room which is usually between 68f and 70f, exhaust out a bedroom window. would it be better to shut the passive vents and install an intake fan with a pre-filter? hoping to keep bugs out as well.

 

[SourBubbler]

You really need an air intake. No matter how big your fan is, it will never bring in enough air with just passive air exchange. Cut a 6 inch hole in the side somewhere for an air intake, hook that new fan up and you'll have plenty of outside air.

 

[TNTBudSticker]

Rule of thumb is you need .3 per wattage to remove heat.

400hps x .3 wattage to remove heat is 120 cfm,one would need 300cfm of carbon filters.Removing heat,smell.

1000 hps x .3 is 300 cfm.

All the carbon filters in the growbox? Because if so,you can open an passive air intake and exhaust everything through the filters in the box and expel out of the box and really shouldn't have any smell.
I don't go for the inline fans but use a house fan attached with its proper cfm rating.

Really shouldn't have any problems with the new fan at its lowest setting.

 

[joe fresh]

i'm upgrading my inline fan which will be used to cool at least 1000w if not 2 600w HIDs and will likely either be going with 710CFM hyper fan stealth by phresh or the 932CFM max-fan with 3 speed setting ranging from 749CFM, 849CFM, 932CFM. whichever i choose will be installed in a foam-padded box and connected to a duct silencer in hopes i will no longer be bothering my family. generally i run a 6" inline fan to scrub and cool the hoods as well as a portable A/C to help out the fan when necessary. not a sealed room so probably not the most efficient.

some of my concerns are whether or not the upgrade to an 8" fan is overkill considering the size of the tent and how much ducting will cut down on the efficiency of the fan. i don't see any way around at least 10'-20' of ducting before it will be vented outside which is why i'm considering over twice my usual rate of airflow.

another concern is not using an air conditioner. i need to cut down on noise as much as possible so unless absolutely necessary, i would prefer to scrub and exhaust the room with a single 8" fan. it will be hot here this summer but the area of the house i grow in is usually about 70f tops so i figure with enough air exchange, mid 70s to 80s shouldn't be too hard to achieve.

only other configuration i can think of is a loop of outside air for the lights, a fan with a scrubber running inside the tent at all times, and the portable A/C as a sealed system rather than using exhaust fans.

any experience or input on this type of thing? seems most people either recommend a sealed tent with A/C or just run a single fan to scrub and exhaust the heat from the lights. my main concern is noise and electricity usage. the only reason i'm re-doing things is because of complaints over pumps/fans. any help is appreciated!

i have a 4.5x9.6 foot tent...i use a max fan HO with the 3 speed settings...on level 1 it sucks the shit out the walls of my tent...like seriously...i wish it was a bit less strong...looks like my walls are caving in when its on lol....that being said it works amazing and is much quieter than my 12" vortex that i use in my flower production rooms

if i were you, i would invest in the 8"maxfan HO...i have no restrictions or bends and my total ducting before and after the fan is about 5 feet, if your gonna add a silencer and have longer ducting and more kinks, it will reduce the flow of the fan...leaving you the option to turn it up to 2 or 3 if you like...

i have my tent in a room and vent outside when i can, or ill turn the a/c on when its really hot out and i need that extra cooling....my hoods are open batwing type, no air cooled

 

[Granger2]

A variac won't cause more noise. An intake fan will cause more noise. If you use passive intake totalling twice the square inches of your exhaust, you'll have plenty. Doesn't matter what shape it is. An 8" fan has 51 sq in of area. You'll need 100 sq in of passive intake. That can be a square that is 10x10," or 2 8" round. I'd probably go with 12x12 with screen wire over it.

If you use straight metal duct pipe everywhere that it's practical, you'll get much better air flow than flex duct, but I would insulate it cuzza the noise. A larger fan, variac-ed to lower speed will be quieter than a smaller fan. Good luck. -granger