This step is for MK2(S) only, go to the previous steps for MK2.5(S) or MK3(S)

Do not use the Noctua coming with your Prusa printer, it is not strong enough for the Hemera. As of today the E3D fan specs are unknown and so we recommend to use the fan that comes with your Hemera.

Hemera comes in 12V or 24V version. The 24V version has a 24V hotend fan that needs to be used on MK3(S) Einsy Rambo. The 12V version has a 12V hotend fan that needs to be used on MK2(S) or MK2.5(S) Rambo Mini. Double check the voltage of the hotend fan on its sticker.

MK2(S) only: Connect the hotend fan to the Rambo Mini just like on stock Prusa MK2(S). Make sure the polarity is correct.

+12V goes to top pin of the hotend fan connector

Ground goes to bottom pin of the hotend fan connector