I have Vivosun 8x8x80 tent and a Vivosun 6" 390 cfm exhaust and carbon filter. I want to duct in air from outside. 6" intake vent to 6"flex to a 6" bug guard. Close off the 2 tent side ports at the bottom. With only a 6" intake is that going to be a adequate volume of intake air.
From what I’ve been learning here, you want to be able to completely exchange to air in your tent in a minute. Yours for example is 8x8x6.6= 427cubic feet. Your fan does 390 cubic feet per minute, so it’s a bit small. I don’t think it’s the size of your ducts, it’s the fan capacity.
I don’t want to do you wrong, so I’ll tag a few peeps that know their indoor just to check my math. @kellydans @Myfriendis410
@Northerlit Oh ,I’m sorry it’s a 4x4x80 tent like in the title
I would give it a try, you may end up running exhaust fan on the high-speed to keep that negative pressure inside tent. You may end up playing around with adjustment on the intake and exhaust to get where you need to be. The carbon filter will also play into the CFM As @Northerlit mentioned exhaust fan a little under sized for that big space. I use a 6-inch in a 4 by 4 space I’m on the low side of medium speed.
I just seen your update on size you’re good to go.
In that case, 4x4x6.6=106 cubic feet, and a 390 is more then enough, like 3x’s enough. My only question would be your intake. Again from what I’ve learned on the forum is you want to create negative pressure on your tent, think walls pulled in slightly from the suctioning of the outgoing fan ventilations pull, while also having adequate air flow intake to make sure your not creating to much of a vacuum. I’ve seen a lot of 6” out 4” in with the speed slower on the intake vs to out.
@Northerlit should I get a inline fan for the intake ,to decrease the negative pressure
Usually your exhaust fan is going to run 24/7 at a higher speed to maintain negative pressure inside tent, If you’re using a intake fan. it will set at lower speed. You will just need to adjust on the variable speeds and find that happy spot.
That’s my understanding of how tent grows work. You want to pull out all that hot air while also introducing fresh air, which keeps your temps and humidity in your tent within the good range. Not enough airflow = hotter tent.
I would give it a try without buying an intake fan and see how it goes before putting plants in. Run your tent for a full 24 hrs and watch temp and humidity with lights on and off. When you do introduce plants your humidity should increase naturally slightly.
Are you pulling fresh air from outside, do you live in a hot or cold climate?
This is what I’m trying to do .I’m in the Midwest .The cool part of the day is around 80-85F. My grow tent is in the garage is hot as hxll. I got the exhaust fan duct ran to the gable vent. And I cut in a 6" intake vent. I’m going to duct this vent directly into my tent and close off the 2 side tent vents to isolate the hot garage air. What I was worried about is the 6" intake is too small to keep up with the exhaust.
I see you are pulling from outdoors. Keep in mind outdoor temps transfer to your tent.
@Northerlit I know ,but it’s cooler than the air in the garage. I’m thinking I should’ve went 8". Fxck I just put a 6" hole in my garage LOL. I just ordered some 6" flex duct and a bug shield. I hope this works.
Full air exchange once every 2 minutes is plenty
Do you have access to a basement?
Well shit lol if you put a hole in the garage go with that, just keep in mind your ambient garage temp and outdoor temps could play a factor on tent temps. Might need a small ac for summer heat and a heater for winter.
Basically I just want you to be aware of the temperature inside your tent.
I’m just giving you info I’ve learned from countless hours reading through this forum.
@Myfriendis410 & @kellydans are waaaaaay more knowledgeable.
I grow outdoors lol so the info your getting from me is not from experience.
I’ve grown for several years in a garage in SoCal and fight both extremes of temperature (or as extreme as you get in SoCal). For my next setup building a plenum to house dehumidifier, A/C, heater etc to ‘pre-charge’ the intake air.
@Northerlit I’m growing 4 amnesia right now and they laugh at 90F, Lights are off during the hottest parts of the day,but I would love to get my temps below 80F
Will you be using a heat pump or central air for that?
That looks clean as hell, maybe you could adjust your light cycles on future grows to have lights on at night and off during the day.
I would think a few bends in your flex pipe would keep that light to a minimum.
@Myfriendis410 hollycow ,if i run my intake to a electric heat VAV .I can grow outside all winter. WOW