mjez

my heater/AC fan few days ago started to make irritating sound like it's rubbing against something but after 3 days it stopped. I made an appointment for service while it was still doing it but now after it stopped I have a feeling dealer will say they can't hear anything and to bring it back when it happens next. Should I take it anyway or should I cancel my appointment to service and just take it out there next time it happens?
anyone else expierienced this problem?