Cooker cooling fan

Earlier this year we took delivery of our new Lunar Quasar 462.  To my suprise I discovered that whenever we used the cooker (oven or hob), after a few minutes a fan starts up, I presume for cooling puposes.  This is a bit of a pain because of the noise but especially on a CL without mains electric where we are dependent on the battery.  My last caravan (a Buccaneer - 19 years owned from new) did not have a cooling fan incorporated into the cooker and we never had any trouble with that.  Are cooling fans standard now?  Why is it needed - has the quality of the insulation around the cooker been reduced?  This really bugs me and if anyone has any answers I would be pleased to hear them.  Am I stuck with this for ever?