How to Dry Filament in the AMS 2 Pro (And Can It Dry While Printing?)

This is a researched guide based on Bambu Lab’s wiki and store pages as of October 25, 2026. Bambu changes drying features with firmware, so check the wiki before you rely on a detail.

How drying works

The AMS 2 Pro has a built-in heating and drying module that reaches up to 65 °C. Bambu says this dries most filaments. During drying, moisture leaves through vents at the bottom and rear, so keep them unblocked. Bambu’s store text says the spools rotate during drying for more even results, and that RFID sets the drying settings for official Bambu filament.

Steps on X1 and P1 printers

1. Update the firmware. Drying on X1 and P1 needs a firmware update (the wiki dates it to the end of April 2025).
2. Plug in the Switching Adapter to the AMS 2 Pro. Without it, the printer shows an insufficient-power notification, and the power icon is grey. It turns green once connected.
3. Add desiccant. The wiki says the AMS 2 Pro uses color-changing silica gel (yellow turns purple when saturated), placed at the middle-back section.
4. Place the spool on top of the AMS 2 Pro. Do not load the filament into the feeder for drying. If it is loaded, you get a notification asking you to remove it.
5. Close the top cover for an airtight seal, then turn on the printer.
6. Open the drying page. On an X1C, go to Filament and tap the AMS humidity icon, or use settings and select AMS Drying. On a P1, tap the notification that the AMS is available.
7. Choose the slot and settings. For Bambu filament, RFID sets temperature and time. You can also set them manually, up to 65 °C. The wiki gives PLA at 45 to 55 °C for 6 to 8 hours as an example, so check your filament maker’s data sheet.
8. Start drying. You can watch temperature, humidity and time remaining on the screen.
9. Let it cool for about 5 to 10 minutes, especially after high temperatures. Then check that the filament feels smooth, with no deformation, flattening or gear marks.

Filaments that need more than 65 °C

Bambu says some filaments need a higher temperature than the AMS 2 Pro reaches and may not dry completely. In that case you see a notification suggesting the AMS HT. Bambu’s store marks several materials, such as ABS, ASA, PA and PC, this way.

Can it dry while printing?

Bambu’s own pages do not say the same thing, so here is each statement:

Source	What it says
CA Store	Drying is not supported for an AMS 2 Pro or AMS HT actively involved in the print job, including units used for auto-refill. It also says printing while drying is not yet supported.
EU Store	The only supported case is when the printer prints from some units (or an external spool) and dries in units not involved in the current print.
Wiki FAQ	On H2D and H2S, if the printer is printing and powering one AMS 2 Pro for drying, drying power is reduced automatically so printing has priority. Bambu recommends the external adapter for best results.
X1/P1 wiki	No statement found about same-unit drying while printing. Drying needs the firmware update and the adapter.

Owner reports differ by printer, but those are reports, not Bambu statements, so check your own printer’s firmware notes. For power requirements across printers, see the AMS 2 Pro power adapter guide.

After drying

If the filament is dry and undamaged, load it and print. To store it instead, Bambu says to use airtight containers with desiccant.