I have an easy and cheap mod for the FC-30.
Remove the top and bottom covers. Cut the red wire to the fan and solder a wire from it to the positive terminal of RL2017.
This will allow you to turn the fan on and off from the "Tune" function in the menu.
When the ATU is not in use the fan will be off, when you push "Tune" the fan will stay on until you turn the ATU back off again. This way you can have the fan on during TX and turn it off for RX or VHF/UHF work.