US: https://us.snapmaker.com/products/part-cooling-fan-adapter-board-2-pack-for-snapmaker-u1
EU: https://eu.snapmaker.com/products/part-cooling-fan-adapter-board-2-pack-for-snapmaker-u1
Global: https://shop.snapmaker.com/products/part-cooling-fan-adapter-board-2-pack-for-snapmaker-u1
Detach the toolhead from toolhead swapper, then power off U1.
Manually move the toolhead swapper to a convenient position for operation.
Use H1.5 hex key to remove the 4 screws, replace the adapter board, and then tighten the 4 screws.
Align the new part cooling air duct with the guide rails at the bottom of the toolhead swapper, then install the air duct.

After following the troubleshooting steps, if you find it difficult to resolve your issue, kindly submit a support ticket through https://snapmaker.formcrafts.com/support-ticket and share your troubleshooting results with some pictures/videos.
Our dedicated support team will be more than willing to assist you in resolving the issue.