A loud fan noise when your Glowforge starts printing can be caused by:

• Debris or build-up in the air assist fan located on the back of the printer head
• Debris or build up in the exhaust fan located in the back-left corner of your Glowforge

The good news is, there's a way to fix this! Please review the following articles to clean your fans:

• Steps to clean your exhaust fan can be found near the bottom of the guide to Clean Your Glowforge
• Steps to clean your Air Assist fan can be found here.

If you run into trouble while cleaning your fans, or if cleaning them doesn't resolve the trouble, please contact Glowforge Support and give us as much detail as possible about what went wrong. We'll be happy to help!