5x10x7 grow tent ventalation set up

integar94

New Member
if i was using 2 1000w air cool hood, would using a 500 +cfm exhaust fan be enough to keep the temp in the safe area. the temperature outside my temp r like 75f year around. Any advice would be appreaciated thanks.
 
The rule of thumb is 200 CFM for every 1000 watt. So 500 CFM is more than enough. Your lights are going to put out some heat still. So what some people do is connect a carbon filter to your hood and then attach your inline fan to the hood. Then you can hang your carbon filter at the ceiling of your grow area so it is pulling out the hot air through the hood and then exhausting it out of your grow area. This will create a negative pressure in the room and it will draw in some of that 75 degree temp you have outside of the grow area. The only downfall of this set up is that you will be running your carbon filter more than you need to so it will need to be replaced sooner and if you have any supplemental CO2 in the room it will be exhausted out with the heat.
 

integar94

New Member
O thanks for the info bro! So it basically like carbon filter-inline fan- hood- hood - exhaust fan? And does the inline fan has to be the same cfm rating as the exhuast fan
 

smokeymcpot.

New Member
I would use at least 745 cfm and just have a dim controller to control temps. Better to have more then less. Tents can get hot sometimes
 

smokeymcpot.

New Member
That set up with 2 fans is a good one also. Rule of thumb for that kind of set up is to have the exhaust fan bigger than the intake to maintain negative pressure air flow.

Ex. Carbon filter>> hood>> exhaust fan 745cfm towards the ceiling. Then have your intake fan ~445cfm towards the floor to bring in coldest air.

Another way you could do it also. I prefer this method. You run the same two fans I just mentioned in a separated configuration. Use the 445cfm only for the lights. And use the 745cfm only for exhausting the room. Two separate duct lines.
 

integar94

New Member
Smokey but if I did two separate ducting, wouldn't the weaker cfm inline fan do a poorer job cooling the light?
 

smokeymcpot.

New Member
No it would work fine just for the lights. They only contain maximum 5 cubic feet of space so a 445cfm fan is exchanging the air in the hood 20 times a minute if the hoods have 25cubic feet. I should have shown example.

Ex. Light line

outside of tent intake>> light>> light>> 445cfm fan>> exhaust out of tent.

Ex. Room air exchange line

Intake at the floor of tent (booster fan optional)>> exchange and circate fresh air inside tent>> 745cfm fan>> carbon filter.

Hope that helps. I ran that configuration in my 4k last winter and the fans weren't even running full speed. Perfect 76°. I was pulling my air from outside which was about 50-65° tho . Same configuration doesn't work in summer months with the temp increase of 10-15°, outside temps 60-75° .
 
Top