do I leave my exhaust fan on?

[Rayman522]

A couple sources say to leave it on all the time. But why cant I hook it up to a enviroment controller and it only comes on when the humidity or temp is too high? would that be enough fresh air? room specs are 7 ft long 3ft wide 7 feet tall. only using flourescents.

thanks
Raymankiss-ass

 

[mannurse801]

What kind of fan are you using to draw out?

 

[Rayman522]

What kind of fan are you using to draw out?

A 4 inch 171cfm

 

[mannurse801]

A 4 inch 171cfm

That's a pretty strong fan for a small area. You should be fine with cycling your exhaust, shouldn't be a problem.

 

[7th1der]

That's a pretty strong fan for a small area. You should be fine with cycling your exhaust, shouldn't be a problem.

If a 171 CFM is a strong fan for a 7 ft long 3ft wide 7 feet tall area, am I trippin for trying to get a 197 CFM Soler & Palau for my little cab?

 

[klmmicro]

I am looking at the same thing. I will probably go with a standard duct fan that runs to cool my light, but am considering setting up a t-stat to control the internal temp of my tent. I was talking with a few growers that told me 200 CFM is about perfect for my 3.25x3.25x6.5 foot tent. My dad did the calculation and sort of laughed...that would exchange the entire space air in about 30 seconds.

My thought is, environmental control on the main exhaust fan and then have a circulation fan to keep things moving internally.

What type of controls are you considering?

 

[7th1der]

I am looking at the same thing. I will probably go with a standard duct fan that runs to cool my light, but am considering setting up a t-stat to control the internal temp of my tent. I was talking with a few growers that told me 200 CFM is about perfect for my 3.25x3.25x6.5 foot tent. My dad did the calculation and sort of laughed...that would exchange the entire space air in about 30 seconds.

My thought is, environmental control on the main exhaust fan and then have a circulation fan to keep things moving internally.

What type of controls are you considering?

Not sure yet! Wanted to get the fan first.

 

[Fuzzotany]

I use a unused un-cooled, un-heated room and the temp fluctuated a lot so temp control is a must for me, I got mine from discount-hydro.com but this one in the link's cheaper.

http://www.plantlightinghydroponics.com/cap-tmpdne-adjustable-heatingcooling-thermostat-p-360.html
warrantied for 3 years

 

[dhhbomb]

u wouldnt have to have it all on all the time but every like 5-10 minutes so u can have and exchange of air so the plants have fresh air

 

[mannurse801]

If a 171 CFM is a strong fan for a 7 ft long 3ft wide 7 feet tall area, am I trippin for trying to get a 197 CFM Soler & Palau for my little cab?

I forget where, but there is a calculation to use to find the right CFM for the cubic feet of your room. As long as I get 4 good air exchanges per hour, that is all I need, but I have a cool room, and lights bring it up to good temperature. Just calculate, 7x3x7=147. So a fan of 171 cubic feet per minute is recirculating your air a little more than once per minute basically...

How big is your box?

 

[sandmonkey]

I have my fine wired to a thermostat, so if it gets too cool the fan shuts off.

As long as there is air intake vents, you can leave it running all the time.

 

[Twistyman]

A couple sources say to leave it on all the time. But why cant I hook it up to a enviroment controller and it only comes on when the humidity or temp is too high? would that be enough fresh air? room specs are 7 ft long 3ft wide 7 feet tall. only using flourescents.

thanks
Raymankiss-ass

More a matter of how many plants in an area ...IMO....I turn my off during dark periods..(2 plants)..

 

[LinearChaos]

I have a fantech fr150 243cfm fan in a Homebox L (40"x40") with a 400w hps and I leave the fan running 24/7. It works great, pulls the sides or the tent in so I know there is good suction/airflow, and it's one less part I have to buy. Haven't had any issues so far, even when I was in veg and the light was on longer.