I’m sorry for the trouble with your fan. Over time, residue from printing can collect on the fan. This causes it to make more noise spinning than it did before.
I have a method you can use to clean your fan.
First, you’ll need to obtain a can of 3M Novec Electronic Degreaser, which you can purchase from Amazon or Digikey.
That page will walk you through the cleaning process. Brief summary:
Turn off and unplug your unit and move it outside. Make sure it’s in a location where it has power and Wi-Fi
Using the fan maintenance page, you’ll be able to turn the fan on
Following all manufacturer’s safety instructions from 3M, spray the degreaser into the fan while it’s running for approximately 5 - 10 seconds, or until the fan is clean.
When you’re done cleaning, turn off your unit to stop the fan, and return it to its usual home. You should now see considerably better performance from your exhaust fan!
Please let us know if you have any questions!