I have an 6" inline fan set up with my F1 Ultra and it works well in pulling out all the fumes.  However, does this damage the fan already in the F1 Ultra?  It's definitely sucking out more air than the internal fan could ever move.  I noticed some machines have controls in the software for the internal fan speed but I don't see that option in any of the F1 Ultra menus.  Am I missing something?