mmm esc help in e revo running a dx 3.0 tx

[brainanator]

make sure the trim is set to zero.
the fan being on full bore is normal, it's a check to make sure it works during ESC start up.

Just to make sure, you're holding full throttle on the transmitter when you turn on the ESC right? in order to get into the calibration setting on the ESC.