Fan + Filter vs Tent Size

Just multiply your L*W*H to get your total cubic feet(meter). Compare to the fan you have and how many cubic feet(meter) a minute it flows. Here read this, it'll help.

Ventilation FAQ

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The aim is to have all of the air in your tent replaced every minute. It should state on your fan how many cubic meters per hour it can blow. Then you add 30% to account for the inefficiency of the fan and to remove a little more air in the tent than is being replaced, this creates a negative pressure (basically, the tent sides suck in because the pressure outside the tent is higher than inside the tent.

This will cause every hole, seam and crack in your tent to suck in air, so that the air inside your tent isn't going to leak out because of the lack of pressure.

Be sure that the fan you are using is a proper fan and not a 'booster' fan and filter combo. They look like this:

They aren't good with any type of pressure and are not meant to be used as the main source of extraction. If you have a long extraction pipe or lots of bends then you can put one of these boosters half way up so that the air maintains velocity.

The fan you want will typically look like this:

Remember too, the filter also has a limit on how much air it can have pass through it so you'll need to get the appropriate filter with the fan. Enjoy the journey

 

That's fine too, just not the first picture I showed you. Looks like a nice noise reducing fan you got there.

 

I have a 210 cfm case can two put together each 110 cfm with a can lite filter 150 cfm
In a 4x4x6.5
Works good no smells no issues probly the bare minimum in terms of ventilation and it gets hot if ur not careful I have a 250 watt cfl I have to unplug just let my mars 2 400 run when temps get hot

 

'two put together' - what do you mean by that? You just doubled them inline? That's not going to make it 220 mate, it means it'll move 110 twice in a row.

 

So your dimensions require that it needs a 135cfm minimum, so the fan is a little under. What type of fan are you using? Is it something that looks like this? [EDIT] getting mixed up between threads, I alreadys asked you

 

This is my fan and filter had to find a photo 3D printed flange I got em used so I’m just guessing lol but looks like it got matching clips for my t5 lights on tent poles made out of same pink plastic
I think it definitely moves more than 110 cfm when put together feels more anyway
they are separated by 6 inches of 4 inch pipe right now low wattage and don’t have to insulate them for noise can talk on phone next to them
They 80 bucks new a piece i think fancy case fan I got em used with my tent and lights good deal

 

It would be more than 110, but not by much, not double and certainly not 'more than enough'. I have a 220m3/pm rated for my 100m3 tent, I control the pressure with the inlets.

 

What is the height of your tent, let's calculate what you need...

 

And regarding your pm, the fan and the filter will state it's diameter, the typical diameter is 125mm, so you get a pipe with 125mm diameter and a filter with 125mm diameter so they all fit together. You can get different sizes but then you'd need a flange to adjust for the difference and that's more money.

 

You want you exhaust to at minimum to replace the air in ur tent ever 3 min not every min. I had a 4” fan in a 3x4x6’ tent and it had to much negative pressure. I have my exhaust all the way down on a speed controller and it still sucks a bit to much

 

107.2 cubic feet(your tent). Most 4” I’d guess are rated around 150-173 cfm. It should do u good