Clues that you may need to clean out the blower (fan wheel) in your Asko dryer:
– The dryer heats but takes a long time to dry the clothes. Also see this page.
– The dryer makes a disconcerting rumbling noise and/or vibrates while running.
Just be careful in there, you never know what you’ll find. You may even run into the dreaded dryer blower lint rat:
NOTE: I am a professional– do NOT try handling the lint rat like this at home!