The Convection Fan may operate/run during both non-convection and convection cycles:
If the Fan/Air Movement noise is reduced or stops with the oven door open the source of the noise is the convection fan, the convection fan will stop running with the oven door open.
It is normal for the convection fan:
To operate during preheat for both non-convection and convection functions.
Turn off when the oven door is opened.
The convection fan will come on immediately on all Electric convection models:
During preheat or when a convection cycle is selected.
It is not normal for the convection fan:
To operate with the oven door open.
To make a rubbing/metal-on-metal noise when operating.