Fan modifacations

Fman

I got this 8" duct booster fan the other day. I got it from a ac supply place around the corner from the house. It was only 29 bucks. It's a nice little unit. You can get the same from Home DePot, only a little more $. It spins at 1750 rpm's and flows 500cfm. If you changed the fan blade from a 4 blade, to a 5 blade, and say rewound the motor for more rpms, I would think it would flow better. Grainger sells a 5 blade fan for $2.35. All that being said, has anybody tried to do something like this? or any other ideas about increasing flow?

GSR

Hey Fman,
I would think the fan you decribed is plenty, to supply a decient sized room. I use a 6" duct fan to draw in cool air for my 3'x8'x6' room. I use a 6" CanFan + an odorsock to pull air out. With good sucess!
What size is your room?
togp625.jpg togp1625.jpg

whitetrash6

rewound the motor? please explain

Framster

I went the low budget way a few times, although I've never actually bought a "booster fan" which is designed to assist a blower fan (in addition too).

I have found out through trial and error that a squirrel cage blower is better, as it does not lose as many CFM's due to back pressure / flow restrictions.

While a Centrifugal fan/Blower (ie. Can Fan, Vortec etc.) works best.

I've had 1500 CFM attic fans (like your booster) work worse than a 400 CFM squirrel cage fan.

I've learned my lesson.

Either a Squirrel Cage or preferably a Centrifugal fan. As there is nothin' worse than tryin to keep your buds cool. when its cookin'

jangel

Nice babies GSR!!!

__________________
Life,
j-angel


My Little Grow LST'ing w/Hardware

My Outdoor Odyssey 2008 BONSAI MUMS

Cloning a Flowering Plant My Little Grow Blueberry

Fman

My room is 4'w X 8'l X 7'h. Last night I spent about 3 hours looking for air leaks in my room. I took smoked some meds. and went out there with some dap sealant and started filling all the leaks. Today I noticed the door to my room stayes closed all buy it's self, never did that before. Good suction, guess that fan works better than I thought.

GSR

Ya I think you'll be fine. The more fresh air coming in the better though.

Fman

Yea , thats why I thinking about inlarging my intake. Right now its a 6" duct running from under the house into the room, where it goes into a plenum with two 6" outlets. One outlet is in the veg side of the room the other is in the flower side. Im thinking of steping up to 8" or 10" but Im afraid of losing my negative pressure. The exhaust is the 8" fan on top of another plenum with two 5" vents, one to the flower side one to the veg side.

GSR

Hey Fman
Do you also take advantage of the coooool air from under the house? I draw in air from under the house that is about 10 deg. cooler than outside.

videoman

You should try the new fan blade. I've used those fans before, with less than stellar results. They do move some air, but the advertised cfm is a crock. The truth is more like half of what they claim, and any resistance only makes it worse.
Peace

__________________