Microwave Fan for Exhaust?

[Leeguana]

We had a microwave that died a few years ago, and today I decided to experiment. I pulled out the fan, connected the two wires coming out of it to an old lamp cord, plugged it in, and voila, it works!

I've been looking for a cheap exhaust fan for my grow cabinet (4'H x 2.5'W x 2'D) and I'm wondering if this just might work. The fan blade is only 4.5" across, but the whole thing must weigh close to 2 pounds. It blows like a mini-jet propeller, and from googling the CFM of microwave fans, it's probably pushing around 200 CFM.

Does anyone have any experience using a microwave fan for their exhaust? From reading on ROI, I've got some pretty decent ideas for a DIY odor control filter, but any tips on how to mount the fan would be greatly appreciated (since I'm severely challenged in the area of electronics). Are there any safety issues I should be concerned about? (for example, when I plug it in, I'm afraid to touch any part of the motor, for fear of being electrocuted, lol). Here's a couple pics of the fan (the 3 screws on the back are where it was mounted inside the microwave):

Leeguana Reviewed by Leeguana on 08-01-2008. Microwave Fan for Exhaust? We had a microwave that died a few years ago, and today I decided to experiment. I pulled out the fan, connected the two wires coming out of it to an old lamp cord, plugged it in, and voila, it works! I've been looking for a cheap exhaust fan for my grow cabinet (4'H x 2.5'W x 2'D) and I'm wondering if this just might work. The fan blade is only 4.5" across, but the whole thing must weigh close to 2 pounds. It blows like a mini-jet propeller, and from googling the CFM of microwave fans, Rating: 5

[anbesol]

i would say fuck it and buy yourself a real fan. You will probably end up starting a fire with that or electricuting yourself like you mentioned before.

[Leeguana]

i would say fuck it and buy yourself a real fan. You will probably end up starting a fire with that or electricuting yourself like you mentioned before.

Yeah, lol, I was actually more worried about burning down the house than self-electrocution. It's just that this little baby pushes so much air, I hate to let it go to waste. :stoned:

[TheMetal1]

I hate to let it go to waste. :stoned:

Yeah, wasting parts from an old junk microwave really sucks...........
unless it ensures you'll never come home to a local fire dept. tutorial on how to put out an electrical fire :wtf:

I would suggest you either:
1) Do a lot of reading or watch videos on wiring
2) Wait for an expert to come blow your mind w/ a simple solution
3) Buy a new fan (my favorite :thumbsup

Not saying you can't wire up a fan, but considering you are afraid to touch any part of the fan/motor might be an indication that you should go w/ door #2. Have fun!
Stay Keep :jointsmile: and Be safe :hippy:

[Leeguana]

I personally like option 2 the best since it's the easiest, but that probably won't happen. I might shoot for option 1. Just to satisfy my curiosity, maybe I'll waste a little money on some ducting and try to rig something up.

Since the screws on the back of the fan that attached it to the housing of the microwave were exposed, I probably won't get jolted with juice. But maybe I'll try plugging it in again, and then toss a live ant or some other bug on it and see if it survives, lol.

I think I can shape a metal bracket, screw it onto the back of the fan (using the holes and screws where it was originally attached to the microwave), and then attach the bracket to the inside ceiling of the cabinet up against the exhaust hole.

Then affix a piece of ducting over the whole thing (for the "housing"). And on the outside/top of the cab, I'll have to cover the exhaust hole with screen or something so no one gets their fingers caught in the fan blade, lol.

I'll definitely post some pics if I do this, cause if nothing else, it should be a "unique" looking exhaust sytem.

[stinkyattic]

You're lucky as shit that fan is directly connected to a transformer, and you got the whole thing... It's STILL not grounded right, though.

Get a real exhaust. Seriously. That thing is not only a fire hazard, but uncaged fans are DANGEROUS. International Cannagraphic Magazine Forums - The perrills of uncaged fans....lol

[TheMetal1]

That thing is not only a fire hazard, but uncaged fans are DANGEROUS. International Cannagraphic Magazine Forums - The perrills of uncaged fans....lol

LOL @ unintentional grow room security. :stoned:

[Leeguana]

I better get a real fan after this grow is done (assuming the house doesn't burn down). They've only got about 3 weeks left in flowering before I harvest them.

I ended up not making a carbon filter yet, since the wife said I could use our room air purifier (it's got a carbon filter, a hepa filter, etc.). It takes care of the smell unless you are standing right next to the cabinet.

I just took some scrap sheet metal from the bottom of the junked microwave, cut a couple pieces to size (I bolted the two pieces together to make a double layer cause the metal didn't seem very sturdy), drilled holes in the metal, and screwed the fan into it. I was going to cut a round hole in the top of the cab for the exhaust, but since this is a temporary fan, I just attached the fan to the hole on the side/top. There's another hole just like it on the side/bottom. I built this cabinet back in the early 90's and kept my Iguana (Joe) in it, so it already has two vent holes (except they're both on the same side of the unit, and they're rectangular shaped, covered in 1/2" wire mesh).

The temp was reaching 90+ and I was having to leave the door open a bit to keep them cool, but with the fan installed, the temp is now topping out at 80 degrees.

Note to self: Get a real exhaust/scrubber system, and remodel lizard cage so it's more suitable for growing.

[SAP420]

Look man, there is a right way to do things and a wrong way. I'm not one with lots of money either but I would rather purchase a fan filter combo which you can get for less than $200 if you shop around..htgsupply.com. hint hint. I don't think its worth the risk of using a fan that is not designed for what you are wanting to use it for. Plus duct fans are specially designed for perfect airflow to get that hot air out as fast as possible while providing a good suction of air to come in. I just bought everything little by little and now my setup is as follows:

1 HPS 400 watt S51 type ballast with reflector and bulb.
1 3x3x6 hydrohut mini
1 170 cfm inline fan with elf filter scrubber
4 GH waterfarms
1 sunleaves 4 outlet air pump for lift systems
4 single air pumps for reservoir airstones
floranova grow
floranova bloom
6" clip-on fan for air movement on plants (still on the way)
1 heavy duty digital appliance timer for fan and light

[Leeguana]

Sounds like you've got a super sweet operation going on there Sap, I'm jealous. But like I said, I've only got like 3 weeks until harvest, and then I'll be doing some upgrading. This is my first grow and I didn't feel I had the knowledge to justify spending a lot of $ in case things didn't work out.

I didn't really pay for anything in my setup, since it was all stuff I already had (except for CFL's, some light sockets, and a $5 bag of soil). I admit I'm a bit of a cheapskate, but I also kind of get off on the DIY way .

I'll definitely be changing things up in 3 weeks, but there is NO WAY I'm gonna spend anywhere even close to $200 for a fan filter combo. Maybe $20 or $30 for an inline fan, and probably about the same for a DIY carbon filter. I'll spend the leftover cash on more and better lights, since I can't make those from things laying around the house. :rasta:

Let me know if you starting a grow journal, I'm very interested to see what the hydrohut setup looks like.