Dual Extruder Firmware

I just upgraded to a dual extruder setup. Immediately after updating the firmware I noticed the Case Fan was running more than normal… After digging into the differences of the firmware I see that …

Marlin_Dual_Extruder_TAZ4:
#define CASEFAN_SPEED_FULL 100 // Full speed for when motor are active
#define CASEFAN_SPEED_IDLE 70 // Idle speed for when the motor have been inactive
#define CASEFAN_SPEED_MAX 128 // Maximum limit for the fan speed so it does not burn out. Use 128 for 12v fans with 24V Power Supplies
#define CASEFAN_SPEED_MIN 70 // Minimum limit for the fan speed where it will start to spin from a stop without a push.

marlin_TAZ4_2014Q2:
#define CASEFAN_SPEED_FULL 130 // Full speed for when motor are active
#define CASEFAN_SPEED_IDLE 0 // Idle speed for when the motor have been inactive
#define CASEFAN_SPEED_MAX 255 // Maximum limit for the fan speed so it does not burn out. Use 128 for 12v fans with 24V Power Supplies
#define CASEFAN_SPEED_MIN 0 // Minimum limit for the fan speed where it will start to spin from a stop without a push.



So my question, is there really a reason to keep the case fan running all the time with a dual extruder? Also is there a reason for lower max speed?

Thoughts / Comments

If I’ve read this right, the idle fan speed for dual ex. is set to 70%?

Yes the current config on the dual extruder firmware, the minimum fan speed is 70.

It doesn’t look like 70 is a %. It looks like it’s a hard number that has a max limit of 255.