Fan should "blow" air or "suck" ?

Hello Guys,

So i had problem with my first extruder and got a new one.

On the new extruder, the big fan is “sucking” air instead of “blowing”, I’m pretty sure that this is not the intention right?

You can clearly see that it is turning counterclockwise on the video

The voltage is positive between the red and black wire, so the connection inside the rambo board is fine, and the red lead is connected to the red one between the fan and the board.

I guess i got a Fan with problem now.

What is the best way to fix it? swap the connection inside the rambo? cute the wires and swap them??


Vitor Henrique

Take the bolts off the fan and spin it over the right way around.

Sorry, just looked at the video. It’s spinning the correct way. You are feeling the back pressure, since the nozzle that narrows the fan down to the proper size won’t allow all the air to go out the small end, some just blows back through the fan.

Want to test this for yourself, take a small piece of paper like a post it note and hold it in front of the small opening at the end of the funnel and see it blows it away and does not suck it in.


yeah, you are correct!


Vitor Henrique