active air intake
- Thread starter joefish
- Start date
Little Tommy
Well-Known Member
Ventilation is always good. The more, the better.
bongrippinbob
Well-Known Member
The only reason you would need an "active" intake as you call it, would be if your passive intakes were not allowing the correct cfm to enter the grow cab. For example, if you have a 500cfm fan, but only enough room to have passive intakes that allow 300cfm to enter you cab, then yes, an intake fan would benefit you.
However, if your cab is designed correctly, and you have a 500cfm fan, with enough passive intakes to allow for 500cfm to enter your cab, then adding an intake fan will do absolutely nothing. But remember, you want some back pressure in your cab, so you would want some where under 500cfm. But not by much. Having a little less air moving into the cab than what your fan is trying to exhuast will keep your smell in your room.
Your exhaust fan can only "pull" so much air out of your cab. Adding more air flow to the cab will not aid exhausting. If you want to boost your cooling ability, add another exhaust fan and add more passive intakes to increase the cfm pulled into the cab.
You can tell if you have enough passive intakes by taking a light piece of paper, like toilet paper, and placing it over one of your intakes. If the paper sticks to the intake hole, then you have negative pressure. Keep adding intakes until the paper falls off. If it falls off, you have one hole too many worth of intakes, and need to cover one up.
So, will active intakes help? In some situations, yes. In others, they will just be a waste. Figure out which situation you are in, and make a decision from there.
Bob
However, if your cab is designed correctly, and you have a 500cfm fan, with enough passive intakes to allow for 500cfm to enter your cab, then adding an intake fan will do absolutely nothing. But remember, you want some back pressure in your cab, so you would want some where under 500cfm. But not by much. Having a little less air moving into the cab than what your fan is trying to exhuast will keep your smell in your room.
Your exhaust fan can only "pull" so much air out of your cab. Adding more air flow to the cab will not aid exhausting. If you want to boost your cooling ability, add another exhaust fan and add more passive intakes to increase the cfm pulled into the cab.
You can tell if you have enough passive intakes by taking a light piece of paper, like toilet paper, and placing it over one of your intakes. If the paper sticks to the intake hole, then you have negative pressure. Keep adding intakes until the paper falls off. If it falls off, you have one hole too many worth of intakes, and need to cover one up.
So, will active intakes help? In some situations, yes. In others, they will just be a waste. Figure out which situation you are in, and make a decision from there.
Bob
