Preheating speed / printer head fan

Vertex 3D Printer Vertex - Your printer, creations, and ideas for im
1

I wonder if it is necessary for the small fan on the print head to run at full speed, while preheating.

There is no plastic fume yet, and the fan dramatically increases preheating time. (try blocking it shortly and watch the nozzle temperature shoot up much faster)

Is there a reason for this slow heating?
Could it start to run at a later stage?

2

It is necessary for the fan to run, since it cools the PEEK isolator.
Not cooling the isolator can lead to stuck filament.

3

Thanks! That is clear.