There won't be a reset on the fan... if there is a limit that tripped, the unit wouldn't allow the burners to come on. If its a newer system, it probably doesn't have a belt either. If it does then its very possible that it broke and needs replacing.
If the motor doesn't have a belt, then voltage needs to be checked to see if the board is trying to tun fan on. If it is sending voltage to motor, then the capacitor needs to be checked. If the motor has voltage, and the capacitor checks good, then the motor is likely bad.