Reverse blade direction mod for battery fan?

[Oasis Maker]

Is there a simple mod for my battery operated fan where I can switch the direction of the blades? Maybe just switching a couple of wires around?

I have had the perfect fan for hanging under my vent, but I've always wanted it to suck the hot air out and up through the vent and not blow it back down.

In searching for another battery operated fan, I came across a really nice one with a separate battery holder that doubles as a charger for your cell phone etc. Anyhow, the owner said that it does not have reverse direction, but on smaller fans with double A batteries, she has had several customers switch the polarity of the batteries and that has changed the direction of the blades??

Huh? (Never work)

Course I tried it anyway in case I was missin somthin' ... and it didn't work.

Scott G.

[eamarquardt]

If you've replaced the batteries back-a-wards, the batteries are making contact with the contacts, and the fan doesn't work I'd say it won't run back-a-wards! I just tried to reverse the wires on a computer cooling fan and it wouldn't run back-a-wards either so it's not unusual.

However, why can't you flip the fan up-side-down realitive to how it is today and then it could run front-a-wards but would suck rather than blow!

Hope this helps.

Cheers,

Gus

[Oasis Maker]

If you've replaced the batteries back-a-wards, the batteries are making contact with the contacts, and the fan doesn't work I'd say it won't run back-a-wards! I just tried to reverse the wires on a computer cooling fan and it wouldn't run back-a-wards either so it's not unusual.

However, why can't you flip the fan up-side-down realitive to how it is today and then it could run front-a-wards but would suck rather than blow!

Hope this helps.

Cheers,

Gus

Yeah, I just wanted to explore that .0001 percent chance that I was missing something after talking to this lady. Some of her customers must be smokin' some powerful stuff.

As far as doing a flip, I would lose a couple of nice directional LED lights and the hang and loop handle that holds it perfectly on my vent would be of no use. I suppose I could drill 4 small holes in the fan and attach hooks and do the same on the ceiling on my tear... but it wouldn't be the best of applications considering the design of the fan.

I also don't want hooks up where my head often grazes while moving around the cabin.

Scott G.

[bobhenry]

The O2Kool fan will !

Simply reverse the + and - and it will exhaust as well as blow. The blade design is such that the exhaust is relative mild. I wired a double pole double throw center off switch to do the reversing. A simple flick of the switch and it will reverse. Note the fan must come to a complete halt before reversing. This may be the problem with the other fans above for they will not reverse if reversed without coming to a complete stop.

I mounted mine in a wall cavity in the gambrel roof of the barn. The fan pulls fresh air in under the gambrel overhang and blows in forcefully to cool in the summer. While heating the trailer in the winter I can generate positive fresh air flow by the modest exhaust mode.

[BobR]

Here is a diagram to I used to wire a DPDT toggle switch to control forward /reverse direction on my base model Fantastic Vent Fan. By using this method I saved over $25 on the cost of the fan



Hope this helps.

[eamarquardt]

Someone is not paying attention! If the fan won't run (in either direction) with the batteries installed back-a-wards (assuming they are making contact), installing a dpdt (maybe even center off) switch WILL NOT make the fan run back-a-wards!

Simply put: Some dc electric fans do not run back-a-wards when the polarity of the battery is reversed.

Cheers,

Gus

[Ageless]

If it uses brushes, it will run backwards. Think about how an electric model train works . . . .

[bve]

It's possible there is a diode in there to prevent reversing the polarity although I can't see why there would be one.