Changing polarity of a fan motor.

[Brian430s]

I was just wondering if anyone has any experience with changing the polarity of a fan motor to make it spin backwards. I know that the better fan housings are designed with the direction of flow in mind. So performance will be altered. I'm considering doing this so that the better looking side is what will be seen. And I don't think that performance will be changed that much. The fans will also be mounted to radiators if that influences anyones thoughts.

 

[ATMINSIDE]

Performance will drop drastically, the blades are shaped for a reason.

 

[Bobnova]

You can't. Not a brushless computer fan motor.

Technically you could, but you'd have to crack it open and make a new PCB for it. Good luck with that.

 

[RnRollie]

just get a ebm-papst fan that runs in the opposite direction
Note that there are a few (industrial) fans that CAN run both ways... they are not suited for radiators thou

 

[Railgun]

Or flip the fan around...

 

[Adragontattoo]

Or flip the fan around...

THIS above all else. I can not think of a single reason why I would not utilize this option over attempting to rewire the fan.

 

[NiHaoMike]

Swap two of the three phase wires going to the actual motor and it will run backwards, that is if you could get to them. Don't expect the fan blades to work particularly well backwards.