Welcome to the forum,
@Deano!
You should definitely hear that fan running in the convection oven! I have a countertop convection oven, that is still working since 1977 (!), and is what made me get a convection oven in my range. I actually turn the ovens off, when removing and checking things, or adding new sheets, as the fan blows the hot air out of the ovens much faster (especially in the range oven), then I turn them back on, once closed again. So if you aren't hearing, and feeling hot air blowing, something's wrong. I assume this is new - otherwise, if it had already been working properly, but stopped, you would have already known how it was when working.
Is this an oven that can also work
without the fan on? Maybe it needs to be turned on...and maybe it's one of those things they had to complicate!