When our fans are dusty we take them to the garage and use the air compressor to blow off the worst of it then take it apart and clean the rest.
Since you can't take it apart, how about taking it to a place where they repair tires and ask them to blow it off with their high velocity air gun. Couldn't hurt to ask and they probably wouldn't charge you for the air or their time. Just a thought.
Since you can't take it apart, how about taking it to a place where they repair tires and ask them to blow it off with their high velocity air gun. Couldn't hurt to ask and they probably wouldn't charge you for the air or their time. Just a thought.