Intake OR exhaust fan?

Which is considered more important?

I've read some people suggesting that exhaust is more important, but that doesnt make much sense to me.

I've been using a really large intake fan that pulls a lot of air, it will both pull in fresh/cold air and new h2o. The room might get a bit colder if i turn it around and use it as an exhaust, but then the plants wont recieve much fresh air.

There's just 1 door opening to my closet and i dont want (and can't because its not my apartment) do any holes to the walls.

In my other grows i've just used the intake, and it has worked ok (i havent done it the other way around so i cant compare yield).

Ideas are welcome, thanks!

it works to make active exhaust... fans shooting air out... and a passive intake...holes near bottom no fan.... look here... this helped me
ROLLITUP FAQ GUIDE

The fan has several duties.... to circulate air (duh) ... cool the heat from the light on the leaves..... cause your stem and branches to become strong.

if you don't care about smell... then what you are doing will be good enough..... but with a smell issue you need to create an enclosure that is air tight with a passive intake ( a hole) and an active exhaust ( a fan sucking air from the veg chamber and pushing it out) this exhausted air should eb pushed through and active carbon filter...

Hope that makes sense and help... my first grow was in a wrdrobe with a huge old square fan from the 80's. I've stepped up a bit since then.

I would be more focused on using it as an exhaust mounted fan, just my opinion. I have not tried to use a intake fan due to not wanting to pressurize my chamber. I use it as an exhaust, pull negative pressure and then have 3 holes of roughly the same size at the bottom of my setup. I chose this because as an exhaust fan the pressure is working with it, not against it. If a fan blows inward it will eventually be having to work harder because it can only push the air so far. Outward and it has no restriction and just pulls air through. It keeps my temps appropriate as well as providing a little extra wind for stem growth. I still have an additional fan in there to add to the stem growth and keep the air circulating constantly so that there is always movement in their which keeps lights from getting too hot and helps redirect my air flow towards my plants. I would suggest this idea just based off personal preference but every setup is different and what might work for me, might not work for you. Good luck

exhaust move out the hot air should still have intake holes thou