Moved fan outside tent. Now I have positive pressure.

T

Texgrowerz

Member
Okay last week I moved exhaust fan outside of tent. House starting to stank up days later.
So I go outside to see vent cover closed, when it was always open and had nice airflow pushing out( hand felt nice breeze).
Now the vent flaps outside suck close and wont open by the outwards air pressure. So nothing is flowing out I assume causing minor smells.... maybe carbon filter isn’t best but still I don’t think it’s that.
Two variables that may have effected this I’m assuming.
1). I added booster fan with ducting as an intake to be able to regulate temps as I wanted to have controller to help drop temps near end of flower.
2). I moved inline fan out of tent and hung on ceiling.

Now when I noticed this I took out intake vent from bottom and closed the vent port back up, to see if the addition of the intake was to much. Well Then the walls pushed out more lol. I always run my exhaust 24/7 on 80-100%.
Am I doing something wrong? Bigger exhaust now?( mines only 3 months old. 4 inch I power off amazon). Can I add a a/c infinity booster fan to help vent it and get negative pressure back?

Man I know it’s long read, I really appreciate the helpfulness I see on this site.
 
Are your sure you didn't get the fan turned the wrong way ? If not your intake fan is moving more air than your exhaust. You either need to slow that Intake fan down or get a larger exhaust.

What size tent and type of light? I had a vivosun 4 inch fan and filter combo that only lasted a couple months of pulling thru the filter. It would exhaust my 2x4 without the filter attached but that was about it.
 
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spliffendz said:
Yeh obviously sounds like fan is the wrong way
Click to expand...

Its an easy mistake to make. When I recently upgraded my closet exhaust fan from 4 to 6" and added a carbon filter, I put in my exhaust backwards. I spent 20 minutes trying to figure out why I couldn't shut the closet door. Finally got it shut and I feel air blowing out from my intake. Took another 10 minutes to realize my mistake. :facepalm: Was super annoying bc I had to move and re level a light to fix it up.
 
ilovereggae said:
Its an easy mistake to make. When I recently upgraded my closet exhaust fan from 4 to 6" and added a carbon filter, I put in my exhaust backwards. I spent 20 minutes trying to figure out why I couldn't shut the closet door. Finally got it shut and I feel air blowing out from my intake. Took another 10 minutes to realize my mistake. :facepalm: Was super annoying bc I had to move and re level a light to fix it up.
Click to expand...
Yeh no, I could be totally wrong, it took me a while to understood what he wrote
 
I do remember setting up my first grow years ago and being totally stoned and dumbstruck as to what went where
 
Texgrowerz said:
Okay last week I moved exhaust fan outside of tent. House starting to stank up days later.
So I go outside to see vent cover closed, when it was always open and had nice airflow pushing out( hand felt nice breeze).
Now the vent flaps outside suck close and wont open by the outwards air pressure. So nothing is flowing out I assume causing minor smells.... maybe carbon filter isn’t best but still I don’t think it’s that.
Two variables that may have effected this I’m assuming.
1). I added booster fan with ducting as an intake to be able to regulate temps as I wanted to have controller to help drop temps near end of flower.
2). I moved inline fan out of tent and hung on ceiling.

Now when I noticed this I took out intake vent from bottom and closed the vent port back up, to see if the addition of the intake was to much. Well Then the walls pushed out more lol. I always run my exhaust 24/7 on 80-100%.
Am I doing something wrong? Bigger exhaust now?( mines only 3 months old. 4 inch I power off amazon). Can I add a a/c infinity booster fan to help vent it and get negative pressure back?

Man I know it’s long read, I really appreciate the helpfulness I see on this site.
Click to expand...

Can you draw a pic of how your setup is I think I understand but also don't get the part about outside vent cover being closed. Is that for your intake or exhaust port?
 
Appreciate the help. Well I can say now when tent is closed walls suck in good, if intake is off. When I turn intake on to test it( on low) walls kinda suck in but not much. So I’m assuming it still has nice negative vpd, which I don’t understand but hey say to kk da care so ehhhh. I’m using a wireless Inkbird as a intake controller
 
Got a laugh. Thanks. I've done dumb shit like that before too. :)

If I can give a tip on why you changed things....
I've been messing with my exhaust a lot lately. I run 2- 1kW hps for flower in a 4x8, so lots of heat.
Unless your intake fan is blowing in cooler air than what your exhaust was passively sucking through, it won't drop your temps.

You'd be better off turning the fan around and pulling more air through your tent and out.

I had to increase my exhaust from 1- 8" to 2, drop my ambient room temperature that my tents are in, all while using air cooled hoods to get my issues lined out. Just figured I'd share since it took me about 2 weeks of frustration and moving things around a million times before I found what works.

Edit...moving the carbon filter from the intake to the exhaust side of the fan also helps to decrease temps. I assume that had to do with "pushing" the air out decreasing air resistance as opposed to "sucking" it through the filter. But that doesn't sound like it will work for your situation sense it sounds like you're venting outside.
 
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.Smoke said:
Got a laugh. Thanks. I've done dumb shit like that before too. :)

If I can give a tip on why you changed things....
I've been messing with my exhaust a lot lately. I run 2- 1kW hps for flower in a 4x8, so lots of heat.
Unless your intake fan is blowing in cooler air than what your exhaust was passively sucking through, it won't drop your temps.

You'd be better off turning the fan around and pulling more air through your tent and out.

I had to increase my exhaust from 1- 8" to 2, drop my ambient room temperature that my tents are in, all while using air cooled hoods to get my issues lined out. Just figured I'd share since it took me about 2 weeks of frustration and moving things around a million times before I found what works.

Edit...moving the carbon filter from the intake to the exhaust side of the fan also helps to decrease temps. I assume that had to do with "pushing" the air out decreasing air resistance as opposed to "sucking" it through the filter. But that doesn't sound like it will work for your situation sense it sounds like you're venting outside.
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I gave that idea( extra exhaust power since it’s only a booster fan) some thought. I have to try that now, I want to have better control over temps and that sounds beneficial. So changing it up for a test day I can do. Thanks .smoke.
I thought that since I can run intake duct to pull air from right literally right next to central air vent, I can pull IN the coldest air. Well that kinda works but not as efficient as I want.
 
I would not use the duct booster at all. For intake they can actually restrict the airflow, added to extraction in the same line as your main fan it will defo impede your main fan.

They are really no good for anything except helping the air along in a slow moving long length of duct.
 
True it seems I don’t need it. I haven’t really had issues with temp management before. I managed my temps before pretty easy, just had to know how open to leave tent unzipped. By doing that I could get temps under control and right on point. 80-83 early flower. Now I stay near 78-82.
I thought I could dump in cold air with Intake to get it to like 76 or 77. To see if I could get colors out and sorta simulate winter( bro science?). And also to be a back up to high temps inside tent just incase. So I can understand why using it as intake fan can be over complicated, or even useless.
@coreywebster your saying that adding to exhaust duct ( goes outside) Wouldn’t be advised as it may impede airflow? It’s an ac infinity booster, so while yes still a booster, this baby has power And looks like good quality for 26$. But if ya think Ishouldnt use, I’ll be the grasshopper and listen
I appreciate your pointers and everyone else’s. As ya can probably tell this thread has been most helpful to me.
 
Nothing wrong with wanting to bring out the colour, cold roots is the key rather than cold air, as far as I know.

Yeah im saying if both fans are in the same line (same duct) then the weaker fan will impede the airflow of the stronger one.
Not seen the ac infinity duct booster, most are shite but possible the ac infinity is a quality unit.
Still the same though, your main extractor will perform better on its own. Unless there is like 20-30ft of duct and then it might be beneficial to have boosters.
 
Blac
coreywebster said:
Nothing wrong with wanting to bring out the colour, cold roots is the key rather than cold air, as far as I know.

Yeah im saying if both fans are in the same line (same duct) then the weaker fan will impede the airflow of the stronger one.
Not seen the ac infinity duct booster, most are shite but possible the ac infinity is a quality unit.
Still the same though, your main extractor will perform better on its own. Unless there is like 20-30ft of duct and then it might be beneficial to have boosters.
Click to expand...
Something works cause that purple clone I have pictured, the mama didn’t look like her, my buddy tripped when he saw I got way more colors out. yeha then ac infinity ones I believe are new. The built quality it pretty impressive. And it’s speed controlled too. But after messing around with tent all morning, I agree I won’t think I need it. I may use it as small exhaust now for veg tent Or maybe use it somehow for drying closet.
 
@coreywebster - bro off topic from thread but I’m curious, whats one simple way to lower root temps? Cold water? Cold airflow? Everything is back to normal now tent is now perfect temp humidity zone. I don’t planned on doing anything else to tent set up, just curious and wanted to ask about that. I’m trying to do the KISS method lol( keep it simple stupid). The intake idea will be swept under the rug haha.
 
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