I'm trying to make a sterile hood for cell culture and I'm using a $20 box fan but after trying it, I found that the static pressure caused by the hepa filter is too high to push air through the filter with a box fan so I'm considering other options for dealing with higher pressures.

I'm considering trying a car's heating fan
http://www.ebay.com/itm/Front-A-C-A...ash=item5661e53a91:g:vIIAAOSwgQ9VzchJ&vxp=mtr
But I'm having trouble finding info about the CFM at various static pressures.

I have no exp. with blowers, so before shelling out the money, I was going to try some AC Cooling Fans which I guess are intended for higher pressure than a box fan.

I have a bunch of 120v AC fans scrapped from somewhere but I was always afraid of ac power (from years of parents telling me not to mess with it...and stories of burning the house down...so I never messed with ac).

Would it be safe if I just twisted the leads of an AC fan directly to a wall plug lead? Would it still be safe if I twisted like 4 AC Fan leads together in parallel?

 

Your parents were right about that. Mine too (Zap -OUCH!).

If your AC outlet has the same voltage and frequency for which your fans were intended and they were intended to be powered by mains voltage (this relates to whether the leakage current to ground is low -if your fans have a plastic frame you need not worry.) by the manufacturer it was intended to connect them directly to the mains then you can do so, and provided your fans don't need a lot of current you should be able to wire them in parallel. Be sure to insulate the connections carefully -use wire nuts, insulated crimps or solder and insulate with electrical tape.

If you don't know whether the fans are impedance protected (can run with the blade held in position without overheating) include a fuse rated at about 2 x the rated current, If three fans, the fuse rating should be 2 x (3 fans x rated current).

And one other thing: Make sure everything is unplugged before touching any bare wire. Good luck!

 

Hi,
doing a twisted wiring of a single fan is not a problem ,as long as the two wires have an insulation.
4 fans twisted also in not a problem too ,just be sure insulated each pair and two distinct lines x4.

 

Cool it works! The cfm is very low though so there's no way this would replace a real blower