Opinion on intake fan for stealth box

[Iron Addict]

Hello guys this Is my first post here on the forum. I've been a browser for awhile and been reading a lot of threads to get familiar with the growing the world.

I have read through many threads on this forum and found a couple in particular that I will be basing alot of my ideas off of.

But here I have a question on ventilation fans.

My main idea was to buy some top quality computer fans but was told from a computer guy today that computer fans are not built to be running 24/7 and that it's not a wise choice to buy them, instead to buy 120 volt fans, do to easier wiring and better durability. Ok cool I took his opinion and did some research and couldn't find hard info on his claim, and to make it worse I stumbled on this fancy intake set up, that I wouldn't mind buying if computer fans are legit..
If you can throw me some opinions, I'd appreciate it.

Link to fan: http://m.ebay.com/itm/231409737752

Thanks guys!

 

[Iron Addict]

The box size I was planning on running is 3x4x7 LxWxH.
It might not be exactly that size toward the end, but will be in that general area. I want to be able to fully screen 2 plants, (scrog) and have a veg and clone chamber, all in one.

 

[Iron Addict]

Also I was going to run LED for lighting for both veg and flower. Done a bunch of research on it and I think if I buy a good set of leds I will be super happy with results. Not rich or anything but I'm not putting a cap on my lighting fund, also doing it by soil. I'm excited

 

[oill]

Also I was going to run LED for lighting for both veg and flower. Done a bunch of research on it and I think if I buy a good set of leds I will be super happy with results. Not rich or anything but I'm not putting a cap on my lighting fund, also doing it by soil. I'm excited

Don't bother with an intake fan, just get one good fan to extract from the top and an oscillator or tower fan to circulate. I recommend a prima klima thermostatic controlled fan to keep your room bang on temp

 

[Iron Addict]

Thanks oill! I'll definitely look into that

 

[TubePot]

The box I built had a intake and exhaust, in the summer you will need it IMO.

The intake fan is dual purpose, draws cool air from the room and blows over the plants, no need for a fan to circulate.

I took off the stand on fan and took screws off that hold the cage together, made hole in cab and put cage back on and used wood screws and screwed cage on to cab. Installed light box and a ac filter at bottom of light box
http://www.officesupplieslane.com/hlshnf0410abm.html

The exhaust fan I used is below
http://www.radioshack.com/cooling-systems#prefn1=brand&prefv1=RadioShack

You can't hear fans at all when running....

 

[Tim Fox]

my box is 2foot by 3 foot by 6 feet tall, I wanted complete stealth, so I went with a german made can fan 6" with a carbon filter that is 6" hole and 14 inches long, then to make it completely silent I read reviews and purchased a Variac speed controller from amazon for $64 dollars, when you have those 3 items hooked together, you dial the speed down with the variac controller to where there is air moving but there is no sound what so ever, I am thrilled with the results for the box, and its about the same size as your box, Plus you only give up about 12 inches across the back wall for this set up, and the fan has a 5 year warranty for $85 bucks on ebay, half what a vortex costs, and the carbon filter has 6.5 pounds of carbon inside, should last for several crops before replacing the carbon inside, read the reviews on the variac 3 amp speed controller on amazon, many grow room guys report the same stealth effects

 

[Iron Addict]

Thanks guys for the links! All this is helping me decide what route to take. Hey Tim what fans did you buy from ebay?

 

[Tim Fox]

I went with CAN FAN brand , they are built in Germany sweet fan too,just Google can fan , I went with the 6 inch, general opinions were to go with an oversized fan and then slow it down , fans get real quiet then but still move air, and they were right,

 

[rory420420]

I went with CAN FAN brand , they are built in Germany sweet fan too,just Google can fan , I went with the 6 inch, general opinions were to go with an oversized fan and then slow it down , fans get real quiet then but still move air, and they were right,

http://www.ebay.com/itm/4-6-8-Inch-Booster-Fan-Inline-Blower-Exhaust-Ducting-Cooling-Vent-HPS-/181144406542?pt=US_Hydroponics&var=&hash=item2a2d0c4a0e

my box is 2foot by 3 foot by 6 feet tall, I wanted complete stealth, so I went with a german made can fan 6" with a carbon filter that is 6" hole and 14 inches long, then to make it completely silent I read reviews and purchased a Variac speed controller from amazon for $64 dollars, when you have those 3 items hooked together, you dial the speed down with the variac controller to where there is air moving but there is no sound what so ever, I am thrilled with the results for the box, and its about the same size as your box, Plus you only give up about 12 inches across the back wall for this set up, and the fan has a 5 year warranty for $85 bucks on ebay, half what a vortex costs, and the carbon filter has 6.5 pounds of carbon inside, should last for several crops before replacing the carbon inside, read the reviews on the variac 3 amp speed controller on amazon, many grow room guys report the same stealth effects

m.harborfreight.com/router-speed-control-43060.html?utm_referrer=direct%2Fnot%20provided ..that one pissed me off also when I found out what they were...

Thanks guys for the links! All this is helping me decide what route to take. Hey Tim what fans did you buy from ebay?

Combine the above 2 items,with a carbon filter and get a reducer if needed for small portals...
Good luck.

 

[rory420420]

Silence tip..hang fans with bungee cords suspending them..
You'll check and go make sure they're still on...

 

[Iron Addict]

Ok my original idea was to get a 4" pvc Tee and at the ends Install 120v computer fans then building a 6" carbon filter out the middle. I found this idea and thought it was the greatest idea ever, being quite and effective (if computer fans are infact as effect as they say).

But you guys are saying with a variable speed controller, I can adjust a bigger fan like the CAN FAN, with very low noise?

I'd like go the route you guys are suggesting if in fact I can control the noise.

Also I still want to go the route of installing a vent fan at the bottom, thought of bring in fresh air into the box sounds better than circulating the air. (Reality I want to do both).

My original post had a link to an intake fan. Would that do justice? Or are their better options?

Thanks guys

 

[budlover13]

I used the radio shack fan posted above. The 120v ones. Used one in a 2x6x5'closet with a passive iintake and one in a diy rubbermaid cloner box. They did just fine but didn't have the power to run through a diy carbon filter.

 

[Tim Fox]

I purchased a 120 volt pc fan from ebay, the fan is nice, but it was woofully underpowered ( I can sale you that fan lol), pc fans are good on very small cabs obviously pc grows or end table or a small dresser grow , budlover is right, they dont have the push needed to go thru much of a carbon filter, that is where the idea of the larger can fans , that are then slowed down come into play, in reply to rory about the harbor frieght speed controller, those are exactly like the speedster controllers and they do thier job by turning the electricity on and off in a pulse pattern, this square wave of electricity is bad for the motors in the long run, and they produce a humming sound in the fan when you have then turned down slow, this hum to me was annoying and not stealth, and speaking of slow , the habor frieght /speedster controllers feel like they have 3 speeds to them, and the slow speed for me was still turning the fan to fast, and there was the sound of whooshing air coming out of the exhaust , even on low, sure you could build a silencer, sure you can put the fan in a box, and do all that extra work, OR you can skip the extra work and effort and just buy the variac speed controller and turn that fan at the speed needed to make it completly silent, no box building, no quess work, just happiness, and this is exactly the end result I ended up with.
I have seen the PVC 4" tee and carbon build, it looks good, But I would guess to small for your box size, or you will have to change the carbon out part way thru? . the 120 volt pc fans are a much better choice to me then you dont have to buy 12 volt convertors , and the fans plug straight into your times as they come with 110 volt plugs on them already, if you do decid to go with the pc fans, go with a light dimmer switch thru home depot for like $ 5 dollars to control the 110 volt pc fan speed, i have seen people hook 2 or 3 pc fans in series to get more draw power, but you reach a point where buying things and testing things becomes expensive! and redundant! you can certainly get away with an inline 4" fan from home depot $29 dollars http://www.homedepot.com/p/Suncourt-Corded-4-in-In-line-Duct-Fan-DB204-CRD/203227157
and then use the carbon filter home depot sales for 4 inch fans $39.97, http://www.homedepot.com/p/Viagrow-4-in-Carbon-Air-Filter-1-with-Flange-22-45-CFM-Exhaust-V4CF/203548977
and then put a speed controller on it, you will be stealth quiet , happy with the results, and Solid too

 

[Iron Addict]

Wow thanks Tim for all that info. It's all very informative and I appreciate how you clarify why you prefer one of speed controllers over the other, definitely clears things up. I went and pulled the trigger on the variac speed Control so it's on its way.

Also Tim I'm not sure when can fan I need to be looking at. I found this one on ebay: http://m.ebay.com/itm/171196429288?nav=SEARCH but I'm not sure if that's the same fan you're recommending.

The carbon filter I was going to make was going to be 4"x18" long. That size isn't large enough to filter my size box?

I'm still on the search for intake fans too, I'll let you know what I find before I make a purchase.

Thanks for all the advice, like you said Tim nobody had the time and money to test everything. That's why I'm on this forum to learn from your guys trial and errors haha.

Thanks u
Guys

 

[Tim Fox]

a 4" x 18" carbon home made is plenty large for your box, go for it, that fan from home depot I was showing you because it was inexpensive, if you can afford the can fan, I would get it, that can fan with the variac speed controller, your going to send me a christmas present next year if you go with that set up, because it is that good when used together . Here is the fan I went with, http://www.ebay.com/itm/Can-Fan-S-600-Inline-Centrifugal-Fan-275-CFM-6-Inline-Fan-Ventilation-Exhaust-/111240885602?pt=US_Hydroponics&hash=item19e6793562

 

[Iron Addict]

Yea I'm not trying to spend a ridiculous amount of money. But at the same time I want to buy reliable and efficient equipment to last me awhile, that said I set a pretty high budget for leds, and ventilation because as far as my box goes that's the most important part of my build. I want over the top lighting and super quiet ventilation and optimal odor control, via the most efficient method. I don't want to do this and that on top of doing that and this. You helped me a bunch by telling me about the fan and speed controller combo. That's one of the major buys of my build and you helped me get what sounds like the best thing I could of found. Thanks man.

If the fan I linked is something you recommend, then I'll jump on that, but if the one you bought is better, I'll get it instead.

 

[Tim Fox]

that first fan you showed me appears to be a "Capacitor started type motor" and some of those types have a built in speed switch or if really expensive a built in speed controller, I bought one like it thru home depot and there are 2 things to know about them, for instance the ebay 6" you linked has a built in speed controller, and it says down in the ebay listing that the fan has 3 built in speeds, with a standard 3 speed motor, this motor will most likely not work with the variac speed controller. 2nd if none of those 3 settings provide the perfect noise level combined with airflow that you need then your stuck with no other choices with that fan. ( makes sense I hope).
one major benefit of that type of fan is small diameter in size, it may only be about 8" thick on the outside with a 6" inside flow thru on the inside.
the can fan I used is made of metal not plastic and has a fully balanced fan blade and swiss made sealed metal bearings (not a sleeve), and a 5 year warranty as well, but the 6" can fan has a diameter just under 12 inches, so I am dedicating the top inches along the back wall of my box for a top of the line fan and carbon filter for the same reasons you are.
Since you have the amazing variac speed controller already coming, my best suggestion is to either get the can fan 6" or a Vortex 6" the vortex is around $140 usa dollars typically while the can fan is $88 on ebay and we could start a whole nother thread debating which one of those fans is better (its that close in quality)
you could always go with 4" ducting and 4" fans and filters, but from everything I read you have to turn them up just a little faster and you have a higher tendency to hear the sould of rushing air thru the smaller pipe.I can say to you with 100 percent certainty that the 6" can fan I purchased coupled to the variac speed controller In real world tests right in my home by me , you will get the ability to make that fan go fast or slow exactly the speed you want it at, I turned my way down slow and the fan is perfectly quiet and moves a gentle amount of air thur my carbon filter and out the top thru a 6" stainless 90 degree elbow, no post fan sliencer needed. no box built around the fan needed. I am going to hang mine with the light hanger yo yo's they sale on ebay, but just for ease of installation more than motor sound,

 

[nomofatum]

You have 84 cubic feet of air in your box. You want to clear the air in your box every 2 minutes. So you need an actual CFM of 42. A 4" 180-200 CFM fan adjusted to minimum setting will easily exceed that even with the backpressure of a scrubber and ducting., it may even be hard to adjust it to run that slowly.

 

[Tim Fox]

I will post pictures in the morning showing the parts and my wardrobe