We have a Bosch BTA3100 tumble drier that's stopped getting hot - the
drum still goes round but there's no heat.

When this happened before (around 3 years ago - the machine is about 7
years old) we called the service engineer, who I'm sure just pulled
the machine out and pressed a reset button. Searching through the
archive of this group, I found references to some Bosch driers having
a red reset button on the back, but I can't see such a button on ours.
I wondered if anybody with knowledge and experience of this particular
model knew where it might be?

Martin