Filter to Fan

BigCityGrow

Well-Known Member
Planning a new grow cab. I'm new to this. I have a 6" Phresh Filter and a 6" inline vortex fan. Do I need ducting between the two? I'm not supposed to hook up the filter right to the fan right? how much ducting do i need between the two to help reduce noise? Trying to keep width of the cabinet down.

Thanks!
 

TCH

Well-Known Member
Planning a new grow cab. I'm new to this. I have a 6" Phresh Filter and a 6" inline vortex fan. Do I need ducting between the two? I'm not supposed to hook up the filter right to the fan right? how much ducting do i need between the two to help reduce noise? Trying to keep width of the cabinet down.

Thanks!
I just bought a Vivosun 6" fan and filter. The 2 of mine slide together nice and snug. here they are in a 25ish" wide cabinet. I cut a hole in the side and stuck the exhaust right out of the cabinet. there is noise from the sheer amount of air it is moving, but other than that, I don't think it's too bad. Of course I don't have to be super stealth either.

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BigCityGrow

Well-Known Member
Awesome thanks. So in some cases its fine to hook up the filter directly to the fan. Stealth is not top priority for me, but I'd still like it to be as quiet as possible, so it's not annoying in the home.
 

TCH

Well-Known Member
this is literally my only experience with it. I am new to the game. lol. I say that if the fan will mount directly to the filter, it should be able to with no problems. I don't think it will change the noise situation for better or worse.
 

BeeRaasta

Active Member
If it doesn’t mount securely without leaks there would be no point in the filter smell wise. If the fan is sitting on top of the filter you could tape it. If they are both hanging, that’s a bit tougher to tape and would prob want a little ducting. Even 8 inches would work.
Good luck man
 

coreywebster

Well-Known Member
You could use a duct collar to connect the two, but some of that aluminium foil tape which sticks very well and is strong would work provided the two didn't move around.
As far as noise goes, acoustic ducting can reduce noise, but 1, 6" acoustic is 8" thick, 2, such a short length wouldn't make much difference.
If you want to lower the noise connect it to a variable transformer speed controller and turn it down. 6" is huge for a small cab, I run a 5" in my 4x4x5 veg tent and turn it down to 2 (of 5) in winter and run it on 3 in summer. That makes a huge difference to sound levels. Also consider that a 6" on full power requires a fair amount of passive intake holes to allow the fan to work effectively without choking it and creating more noise.
 

BigCityGrow

Well-Known Member
You could use a duct collar to connect the two, but some of that aluminium foil tape which sticks very well and is strong would work provided the two didn't move around.
As far as noise goes, acoustic ducting can reduce noise, but 1, 6" acoustic is 8" thick, 2, such a short length wouldn't make much difference.
If you want to lower the noise connect it to a variable transformer speed controller and turn it down. 6" is huge for a small cab, I run a 5" in my 4x4x5 veg tent and turn it down to 2 (of 5) in winter and run it on 3 in summer. That makes a huge difference to sound levels. Also consider that a 6" on full power requires a fair amount of passive intake holes to allow the fan to work effectively without choking it and creating more noise.
Thats great info thanks. Currently planning a cabinet that's internal dimensions are 47" wide, 23" deep, 72" tall. I'll pick up a speed controller as well. I'm still trying to figure out the passive intake. I want to put them in the back of the cabinet. The cabinet sites 6" off the floor, and the back is set in 2", so hopefully it will suck in from the bottom and go up the back, with a 7"x7" square hole, and a filter over the hole. Do you have any thoughts on that?
 

coreywebster

Well-Known Member
Thats great info thanks. Currently planning a cabinet that's internal dimensions are 47" wide, 23" deep, 72" tall. I'll pick up a speed controller as well. I'm still trying to figure out the passive intake. I want to put them in the back of the cabinet. The cabinet sites 6" off the floor, and the back is set in 2", so hopefully it will suck in from the bottom and go up the back, with a 7"x7" square hole, and a filter over the hole. Do you have any thoughts on that?
That sounds a reasonable idea for passive intake, you may want to look into "light traps" to make sure air flows freely but light doesn't escape. Pretty simple to do.
Stay away from cheap controllers, if its not the weight of a house brick its not a variac. You want something that steps the voltage down or the hum that can come from them is worse than the noise of the fan on full. You can pick up a variable transformer for pretty reasonable prices, or you can go for one that has a built in digital control with thermostat so you can input the temp you want and it will adjust the speed accordingly.
 

kingtitan

Well-Known Member
Planning a new grow cab. I'm new to this. I have a 6" Phresh Filter and a 6" inline vortex fan. Do I need ducting between the two? I'm not supposed to hook up the filter right to the fan right? how much ducting do i need between the two to help reduce noise? Trying to keep width of the cabinet down.

Thanks!
Here is my zero smell setup. with this setup all air is always pulled into the space and into the filter. There is only 1 point for smell entry and that is at the filter and fan connection.

I used electrical tape on the lip of the filter so when I direct connect the fan it creates a tight gasket type seal. I then used more electrical tape at the seam where the fan and filter meet. and lastly i i used duct tape over to seal it up even further.

The exhaust end of the fan has a metal clamp covered in duct tape but its not critical with this setup because any leaks past the fans exhaust end will be clean filtered air.

The 6" fan is rated for 460CFM and the CAN 50 filter is rated for 420CFM max for exhausting so I had to get a VARIAC from ebay as a way to control the fan and dropped the voltage down to 90v from its full 120v. with my calculations it should be pushing 350 CFM now or less with the negative pressure and all the 90/180 degree turns + hood. Also reduced the sound level by about 10db

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BigCityGrow

Well-Known Member
That sounds a reasonable idea for passive intake, you may want to look into "light traps" to make sure air flows freely but light doesn't escape. Pretty simple to do.
Stay away from cheap controllers, if its not the weight of a house brick its not a variac. You want something that steps the voltage down or the hum that can come from them is worse than the noise of the fan on full. You can pick up a variable transformer for pretty reasonable prices, or you can go for one that has a built in digital control with thermostat so you can input the temp you want and it will adjust the speed accordingly.
Thanks again. I looked around, how about this guy The Speedstar Variable Fan Speed Controller, I'd link the page but I have not gotten enough "likes" to post a link.
I could not find a digital one, I'll keep looking. Pretty much trying to find the best options for all my equipment, I don't want to cheap out, but I also don't want to get suckered into buying something that looks nice but does not preform. If you know of any digital controllers I'm all ears.
 

BigCityGrow

Well-Known Member
Looks like many bad reviews for that product, but the electronic express variable transfromer gets great reviews for $85, my issue with it is its a desktop style, I'd like to mount it right below the fan box.
 

kingtitan

Well-Known Member
Thanks again. I looked around, how about this guy The Speedstar Variable Fan Speed Controller, I'd link the page but I have not gotten enough "likes" to post a link.
I could not find a digital one, I'll keep looking. Pretty much trying to find the best options for all my equipment, I don't want to cheap out, but I also don't want to get suckered into buying something that looks nice but does not preform. If you know of any digital controllers I'm all ears.
Do not use those speedster type controllers on any motor that is not brush-less. Most even say on the controller that it is for motors with brush (drills, in duct fans etc). Even though some sellers are selling the things along with inline fans (vortex or the one in my post above which have a capacitor in that black connection box). The way the cheap 20 dollar ones work is by starting and stopping the motor hundreds of times to keep it at the desired speed. This causes unnecessary stress and wear on the motor and on the more extreme side the controller could start a house fire when using with this type of fan. Google it, some have used it to save power but it actually does not because the excess power not used is actually turned into heat which equals fire.

The correct type of controller is the variable transformer also called a Variac which will adjust voltage to the fan and actually would save you power. I searched everywhere and honestly the cheapest I could find was Ebay $50 US + Shipping:

http://www.ebay.ca/itm/Variable-AC-Transformer-500VA-Variac-0-130V-TDGC2-0-5-/381200336676.

The seller has a really old era website also and have been selling these for decades. All the other ones I found local or online were in the hundreds of dollars range...

Mine actually arrived yesterday (I live in Canada) and it took only 4 days from them.
 
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