[chabsey]

I've a Neff double under counter oven which is a fan oven in the larger lower oven but there doesn't appear to be a fan in the upper part (when you look inside there's a fan in the bottom oven but none visible at the back in the top one).

When the top oven is turned on I would not have expected to hear the sound of a fan but do, which makes me wonder is the top part somehow also a fan oven?

I've checked the model number online (Bosch appears as the results but apparently they're all made in the one place) and can't see anything saying whether it is not a fan oven.

This is a real mystery and keeping me awake at night so please can someone on earth help me? You're my only hope.

[Alun]

On my double oven the bottom one is a convection (fan) oven and the top one is a conventional one. There's an additional fan that kicks in for both ovens if the bottom one is set to something other than convection, which I think is a kind of extraction or cooling fan.

[coylemj]

The fan in the top oven is probably just a fan with no heating element, it's purpose is to cool the oven down quickly when you switch it off.

To test this, heat up the top oven to a low heat, then switch it off. Leave it for a couple of minutes, then open the door and listen to hear if the fan is running.

[The Red Ace]

this fan motor serves a double purpose , when the cavity gets hot from oven or grill the motor cuts in to cool the switches otherwise they would seize up from the heat, in oven mode the cooler air is deflected down the door glass to stop you getting burned