Welcome to UK420

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more!

This message will be removed once you have signed in.


Maxdank

Running a 6" fan on a 4" carbon filter

Hi all,

 

At the moment i am running a 4" extraction system that draws about 250m3/h.  I have found a good deal on a 6 inch fan that will double that up to 500m3/h. I am wondering if i would be able to run the 6 inch fan with my 4 inch carbon filter using a ducting redactor. With the carbon filter only being a 4" how much of the 500m3/h will i lose? Is it worth it or just invest a bit more and get a new 6" carbon filter. The only thing is my 4" filter is brand new so i feel like its a bit of a waste if i can put it to use.

 

Thanks

Share this post


Link to post


You can use a larger filter on a smaller fan but you can't run a smaller filter on a bigger fan, it'll pull too much air through for it to "scrub" effectively.

Edited by Exhale
1 person likes this

Share this post


Link to post

Mate don't match that 4 inch filter to that 6 inch fan. Unless you plan to run it at a maximum of about 40 percent as it pulls way too much air. Filter won't scrub the air I don't think. What's wrong with your current system? 

Share this post


Link to post

Just get a new filter.  It's always reassuring during a grow to know you've got a new one anyway...:yep:

You can keep your 4" fan and filter and set up a separate tent/room for drying.

Edited by JJJ
2 people like this

Share this post


Link to post
17 minutes ago, ROCKSTEADY6 said:

Mate don't match that 4 inch filter to that 6 inch fan. Unless you plan to run it at a maximum of about 40 percent as it pulls way too much air. Filter won't scrub the air I don't think. What's wrong with your current system? 

Got a 2x2m tent. Needs at least 500m3/h, Temps are becoming a bit of a problem in this weather so i will get a new filter and fan for out take running at 500m3/h and use the 250m3/h fan ive got as another intake.

 

Ive only got 250 intake atm so if i add the other to it it will double the intake so i will have 500 in 500 out.

 

Also im gonna get either a air cooled tubes or reflectors for my lights and they only really come in 6" sizes

Share this post


Link to post
10 minutes ago, Maxdank said:

Ive only got 250 intake atm so if i add the other to it it will double the intake so i will have 500 in 500 out.

Equal suction from the tent and inlet speed won't allow you to have negative pressure.  Smells will leak horribly.  Your inlet should be a good bit less powerful.

Also, in a 2m by 2m space, I'd be inclined to get a bigger extractor (possibly 8 inch).  With a controller it can be turned down and you'll have more control over the environment.  

And bear in mind, a carbon filter reduces your rate of flow by around 25%.

Edited by JJJ
2 people like this

Share this post


Link to post
15 minutes ago, JJJ said:

Equal suction from the tent and inlet speed won't allow you to have negative pressure.  Smells will leak horribly.  Your inlet should be a good bit less powerful.

Also, in a 2m by 2m space, I'd be inclined to get a bigger extractor (possibly 8 inch).  With a controller it can be turned down and you'll have more control over the environment.  

And bear in mind, a carbon filter reduces your rate of flow by around 25%.

 

 

I have 2 a spare 4" fans that runs at 180 each.  I could use these for intake bringing it to 360m3/h and even with a 25% percent loss on the 6" 580m3/h fan it will still be 435m3/h.

 

So overall intake would be 360m3/h

Overall outake would be  435m3/h

 

A difference of 75m3/h.

 

Is this enough negative pressure?

 

 

 

In a ideal world i would like a 600 intake and 800 outake but funds are low this month so only really have £150 to do a makeshift upgrade. I am only 5 weeks off finishing so will be looking to invest a few hundred on ventilation on the next run

Share this post


Link to post
28 minutes ago, JJJ said:

Equal suction from the tent and inlet speed won't allow you to have negative pressure.  Smells will leak horribly.  Your inlet should be a good bit less powerful.

Also, in a 2m by 2m space, I'd be inclined to get a bigger extractor (possibly 8 inch).  With a controller it can be turned down and you'll have more control over the environment.  

And bear in mind, a carbon filter reduces your rate of flow by around 25%.

 

Or i could have a 6 inch filter and a 4 inch filter in there that will be 580 and 250 so 830m3/h outake - 25% = 623m3/h and have 2 intakes of 250 - 500m3/h.

 

So overall intake would be 500m3/h

Overall outake with 2 carbon filters would be 623m3/h

 

Difference would be 123m3/h 

 

Share this post


Link to post
5 minutes ago, Maxdank said:

Or i could have a 6 inch filter and a 4 inch filter in there that will be 580 and 250 so 830m3/h outake - 25% = 623m3/h and have 2 intakes of 250 - 500m3/h.

 

So overall intake would be 500m3/h

Overall outake with 2 carbon filters would be 623m3/h

 

Difference would be 123m3/h 

I'd go with this one.  The more extraction the better.  I'm only just keeping on top of my temps and I'm extracting at 220m3h but with passive intake in a 70 by 70 space.  I hope this will be enough extraction for you in that big space.  Perhaps someone who uses a similar size set-up will be along shortly to advise you.

Share this post


Link to post
17 minutes ago, JJJ said:

I'd go with this one.  The more extraction the better.  I'm only just keeping on top of my temps and I'm extracting at 220m3h but with passive intake in a 70 by 70 space.  I hope this will be enough extraction for you in that big space.  Perhaps someone who uses a similar size set-up will be along shortly to advise you.

Im pushing 84F at the moment and thats with only 1 400w hps and a circulating fan in there. I am only using part of the tent for 8 plants but want too add another 400w for the next run and use the whole tent. At the moment it is impossible to add more light with the heat hitting 84 as it is so i want to add more air and use some air cooled tubes to try to bring it down before i add more.

 

1 person likes this

Share this post


Link to post

as others have said, dont use a bigger fan with a smaller filter as the air wont be scrubbed of the smell.

so you need to get a bigger filter if you intend to get the 6" fan, getting the right ventilation is the one area

that you cant afford to scrimp & save, its your liberty your taking a chance with.

Share this post


Link to post

I have got a new 6" fan and filter that runs at 660m3/h.

 

At the moment intake and outake are both at 185m3/h.

 

Would i be best adding the 660 to the 185 and having 2 carbon filters outakes totalling 845m3/h and just having 1 intake of 185m3/h.

 

Or having 2 intakes of 185 totalling 370m3/h and 1 outake of 660m3/h.

 

So option 1:

 

Intake = 185mh/3

Outake = 845m3/h

Negative Pressure Difference = 660m3/h

 

Or option 2:

 

Intake = 370mh/3

Outake = 660mh/3

Negative Pressure Difference = 290m3/h

 

I have not took into account the 25% loss because of the use of the carbon filters this is just a outline and just looking for some rough advice.

I am leaning towards option 1 as it will better for smell but tbh i smoke indoors anyway so it is not the biggest problem. I am worried that it is to much negative pressure (if there is such a thing) and not enough intake running into the tent so am looking for some second opinions. 

 

Thanks 

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now