6" fan - is this thing powerless?

[weed whacker]

So i picked up a 6" inline (duct booster sort of thing) that is rated at 188cfm. now just fiddling around with it, it sounds like its slowing down A LOT just when i put a 6" to 4" reducer piece on the outlet. this worries me, because my plan is to have the fan hooked up to 4" flex tubing connected to a hole in the closet ceiling, to cool my closet with the 400w hps i'm about to hang up. is this fan gonna be able to handle that reduction to 4"??? i'm not carbon filtering its just an open intake. help!

 

[ForbiddenFruit]

That fan will do minimal to vent your closet, now it is better than no ventilation but you will have to be careful how much restriction you put on it. You will be better off using 6" ducting instead of 4" because the reducer is putting too much strain on an already weak fan. Use minimal ducting without too many twists and turns, also having a fan blowing on the canopy of the plants will help.

Yes this type of fan is pretty much powerless, one of the best investments a grower makes is a nice in-line blower like vortex etc. So go out there and find an In-line blower if you can it will make a huge difference.

 

[weed whacker]

well i can and i have the money for it, i was jut trying to be frugal. also noise is an issue, people i live with would not appreciate buzzing in the walls, and this is in the closet in my room. i need to be QUIET and when i has the guy turn on a vortex in the store, it was pretty dang loud.

 

[green_grow]

yup, those duct boosters are the weaklings of the fan world. maybe do a search on the panasonic whisper fan; lots of people use them in grows.

 

[FreezerBoy]

Consider, also, the S&P. Its similar in shape to a duct booster if that's an issue.

Great Inline Fans (S&P)

 

[weed whacker]

if i return it and get a vortex (for 160 bucks....worth it??) is there a way i can deal with some of the noise from that? wrap it in stuff or something?

edit: should i just get some lumber and plywood and build a cab for the 400w instead? would be cheaper than returning the duct booster and buying a vortex to ventilate my closet.......but then again i would need to put a carbon filter on, and would the duct booster be able to handle that?

 

[FreezerBoy]

Whether cab or closet, return or discard the duct booster. It's useless.

The Vortex will move the most air. That's where most of the noise comes from. If stealth is an issue, move the fan into the attic or another room where no one is allowed to go. Anyone in the room will know it's running and will ask why.

The Whisperfans were getting great reviews until recently. Seems that noise increases after long time continuous use. The link I gave above is someone who gave up the Vortex for a Whisperfan and then, essentially, PAID to have the Whisper taken away in favor of the S&P.

 

[FirstTracks]

There are lots of fan silencing techniques, most of which have dIY instructions posted up here.

From what I remember, here are a few of your options:
1. mount the fan on bungees>cuts vibration noise
2. mount the fan inside a cooler (styrofoam in plastic, usually red or blue) with intake and exhaust holes for the ducting to go through. >this will cut most, or a lot of the mechanical noise of the fan.
3. Duct silencer>variety of methods. Cuts down airflow noise Can purchase these pre-made, looking like super large sport-bike exhausts.
4. Insulated ducting as a muffler.>cuts air flow noise and retains heat inside the ducting and keeps it out of your growspace/outside cab area.
-you can make these by putting 6" uninsulated flex ducting inside of 8" insulated ducting, 4" inside 6" insulated, etc.

 

[hoosierdaddy]

The inline fan will perform far past what you are seeing now if you change all the duct out to 6". Why choke it down? That only goes against what the fan was designed for, so it only stands to reason it isn't going to perform properly with a 4" duct.

I would suggest using something like an S&P for a 400w hid, but don't throw the inline away....you could always cool tube your light, and use the inline as the power source for light cooling only.
But,no matter what you use, don't choke the ducting down.
And if you want to try it first, you can always stack two of those fans together. It will not increase the CFM, but it will increase the back pressure it can handle.
But, if you choke it down to 4", they may still be lacking.

 

[weed whacker]

alright well sounds like ill have to head back to the hydro shop to spend the extra 110 to get a vortex 4". i guess the upside is that it will be able to last me even if i up my wattage, right?

 

[hoosierdaddy]

Just some more of my opinion...but going 4" is a mistake. Especially when considering upgrading.

 

[Whatever]

Just some more of my opinion...but going 4" is a mistake. Especially when considering upgrading.

In general I'd agree with that. One thing I've learned is it's better to get more fan than you need cause you usually end up using it's potential flow in the heat of summer.

Like FirstTracks said mount the fan from a bungee and not hard mount it to the wall or ceiling. This will cut most of any noise that could travel through walls. I mean it's amazing the difference in noise transfer.

Duct mufflers work great and help tremendously. They're pretty cheap off the shelf but also easy and very inexpensive to build.

Speed controllers help reduce noise as others have said it's the volume of air moving through a certain size housing that really generates the noise and my experience is it's more on the intake side of the fan. Vortex are loud and one of the reasons I've used a lot of Elicent fans. One thing I've seen with speed controllers is there can be a tendency to create an oscillation of sorts so best to run fans at full speed really. Both 8" and 10" Elicent fans use the same sized housing and that 10" howls a bit...kind of a lot...lol.

 

[FreezerBoy]

Note with speed controls that some fans, when started at low speed, will produce mechanical noises. If this is true for you, start high and then lower the speed.

 

[Tony Danza]

I just hooked up the S&P that freezer suggests, it pulls far less air than the vortec, but still enough to cool a 400 and is much quieter than the vortec. and about 60 bucks cheaper.

 

[weed whacker]

ideally i want to get enough fan so i can upgrade to a 600 or 1k later down the line, especially given the 40-50 dollar difference in fan price, i dont want to be stuck with one too small later and have to buy ANOTHER one. if 6 or 8 inch could be used to vent into my 4"-6" hole i'll be cutting in my closet ceiling without making so much noise as to keep me up (only a door between it and my bed) or bother the people i live with, that'd be great. im not going to order online as i wanna get this up and going, so it would be a vortex as thats what the hydro shop by me has.

 

[FreezerBoy]

If you're going to upgrade to a 1K, I'd seriously consider going 6-8 inches on the ports. Try running your numbers through this fan-intake calculator

 

[weed whacker]

so as i'm getting less financially ambitious on this first crop, im starting to reconsider and maybe keep the 6" 188cfm duct booster. without any obstructions and an adequate passive intake, should i be able to keep my closet cool with just a 400w running during flowering, and only 200w of cfls during veg?

 

[FreezerBoy]

One way to find out. You need to cut the hole no matter what fan you use. You may want to avoid getting too close into a corner like I did. I can't even fit a 6" can filter straight to the port. Then again, if you're going into the attic, the fan and filter can both go up top.

 

[weed whacker]

anyone care to chime in? if i cut a 6" hole to vent up into the attic and use that duct booster, is it gonna crap out and not vent enough for 400w hps?

 

[green_grow]

it's worth a try, i guess. just get ready to run out and buy a nice, big, vortex if the duct booster doesn't do the job. you said earlier that you may be upgrading to 600w or 1kw in the future, so the vortex will come in handy then. just remember that when you are moving that large a volume of air then noise becomes a factor.