I have an SKR Mini E3 V3 on the way to replace my dead SKR E3 DIP board. I do not want the hot end fan to turn off as I am going to be running a HeroMe Gen 6 setup. As I’ve never had the ability to turn this fan off before, what setting am I looking for in Configuration.h/Configuration_adv.h to disable it?
The fan only turns off when the hotend temperature is lower than 50c. You don’t like silence? 
Either way, the setting is configured using the #define EXTRUDER_AUTO_FAN_TEMPERATURE option. I guess setting the value lower than 50C will keep it on all the time.
My printer doesn’t live at home. Plus I doubt I’d hear a difference between it being off due to the stock Ender 3 PSU fan…
But you think 50C would be ok when the hot end is mounted to a PETG mount on the HeroMe Gen6?
It’s fine. This is the temperature at the nozzle level.
The fan will start in less than 10 seconds after starting the heating process.