Do not treat every Bambu AMS as a filament dryer. Bambu documents active heated drying for AMS 2 Pro up to 65°C and AMS HT up to 85°C. Its current original-AMS materials instead center on automatic material handling and desiccant-supported storage, while AMS lite uses four exposed rotary spool holders rather than an enclosed drying chamber. Match the exact model, printer, power arrangement, filament grade, and reel before choosing an AMS cycle or a separate dryer.
Open Bambu's current AMS 2 Pro and AMS HT drying workflow beside the exact system. Use the named-grade PETG guide for diagnosis, desiccant guidance for storage maintenance, and print-while-drying checks only when the exact connected system supports them.
Which Bambu AMS models actively dry filament?
The answer depends on the exact name on the machine. Bambu makes an explicit active-drying claim for AMS 2 Pro and AMS HT. It does not make that claim for original AMS or AMS lite in the current product and maintenance material reviewed for this guide. Treat the shared AMS name as an ecosystem label, not as proof of a heater.
Use the model list below as a routing check, then open the matching Bambu instructions before operating anything. A newer system's temperature, vent, power, feeding, or compatibility statement must not be copied to an earlier model.
- Original AMS: enclosed automatic material system with replaceable desiccant; no documented built-in heated drying cycle in the current original-model material reviewed here.
- AMS lite: four exposed rotary spool holders for automatic material handling; not an enclosed dry-storage chamber and no documented built-in heater.
- AMS 2 Pro: four-spool automatic material system with active venting, automatic spool rotation, airtight storage, and drying up to 65°C.
- AMS HT: separate one-spool automatic material system with active venting and drying up to 85°C for higher-temperature requirements.
Separate original AMS storage from active drying
Bambu sells and documents replacement desiccant for the original AMS. That supports a storage-maintenance role: the desiccant absorbs moisture from the air inside the closed unit when installed and serviced as directed. It does not establish that the original AMS has a powered heater or that desiccant will remove moisture already absorbed throughout a wet spool on a required schedule.
If a print or the exact filament instructions support active drying, prepare the spool in documented equipment first, then return it to suitable protected storage. Record the full product name because an original AMS, AMS 2 Pro, and AMS HT can sit in the same ecosystem while performing different moisture-control jobs.
Do not treat AMS lite as a dryer or dry box
Bambu's AMS lite product materials show four rotary spool holders around a central body and describe automatic multi-material handling. The loaded reels remain exposed to the room. The product page reviewed for this guide does not document an enclosure, desiccant chamber, heater, drying setpoint, or drying cycle.
Use AMS lite for the feeding and material-change functions its exact printer setup supports. Store idle moisture-sensitive spools in their documented protective containers and complete any required drying process elsewhere. A third-party cover or modification is a separate configuration whose sealing, heating, spool clearance, feed path, and safety cannot be inferred from the AMS lite name.
Use AMS 2 Pro within its 65°C ceiling
Bambu specifies active air vent drying up to 65°C, automatic spool rotation during drying, and airtight storage for AMS 2 Pro. For Bambu RFID filament, the system can match Bambu drying settings automatically. For any other filament, or when the displayed identity is uncertain, confirm the exact product's current instructions and enter only a supported complete temperature-and-time process.
The 65°C maximum is a capability ceiling, not a universal target. Bambu warns that some supported printing filaments require more heat than AMS 2 Pro can provide and therefore cannot be dried completely in it. Confirm the carrier reel's heat limit separately. Do not raise the setting, extend time without support, block the active vent, prop the lid, or add an improvised heater to compensate for a process outside the machine's range.
Power depends on the connected system and number of units. Bambu states that one AMS 2 Pro connected to H2D can use feeding and drying without an external adapter. Its current X1/P1 guidance requires a switching adapter to power drying, and additional drying units can require their own adapters. Verify the exact printer, connection, firmware, and adapter instructions rather than assuming the data cable supplies every drying arrangement.
Treat AMS HT as a different one-spool system
AMS HT is not a high-temperature mode for AMS 2 Pro. Bambu documents it as a separate one-spool system with active vent drying up to 85°C. That can cover exact-grade processes above the AMS 2 Pro's 65°C ceiling, but it gives up the four-spool chamber and still does not establish that every engineering filament, carrier reel, or feed path is supported.
Choose by the complete workflow: required temperature and time, number of spools, reel heat tolerance, printer connection, feeding compatibility, and what happens after the cycle. If an exact filament calls for more than 85°C, a different method is still required. A higher maximum temperature is a capability boundary, not a ranking or permission to heat every spool more aggressively.
Need the process rather than the equipment distinction? Use Bambu's current workflow for the exact AMS and printer, then check the exact-grade drying reference. A shared ecosystem name does not transfer temperatures, power, capacity, or feeding support.
Dry PETG in AMS 2 Pro by exact product
PETG is a family, not one AMS 2 Pro preset. Bambu's current PETG-CF page explicitly documents 65°C for eight hours in AMS 2 Pro or AMS HT. That paired instruction applies to Bambu PETG-CF and its supported carrier arrangement; it is not a universal rule for PETG Basic, PETG HF, translucent PETG, another brand, or another spool.
The current Bambu PETG HF page reviewed here documents 65°C for eight hours in a blast drying oven and 75–85°C for twelve hours on an X1-series heatbed, but it does not state an AMS 2 Pro process on that page. Do not silently borrow PETG-CF's AMS setting. Check the exact PETG HF page, the current Bambu drying workflow, and the machine interface together; when they do not establish one complete AMS 2 Pro procedure, leave it unresolved or ask Bambu support.
Before any PETG cycle, verify that the exact reel tolerates the selected condition, that each loaded spool can rotate freely, and that every material in the shared chamber can use the same supported process. Record the grade, source, method, temperature, duration, load, and result so a future cycle can be compared rather than guessed.
Choose integrated AMS drying or a standalone dryer by workflow
Integrated drying can reduce transfers when AMS 2 Pro or AMS HT meets the exact process and the printer connection supplies the supported controls and power. A standalone dryer can remain useful when the AMS is occupied, when the process lies outside a system's range, when you need a different capacity, or when you want to prepare the next spool away from the printer. Compare those constraints before assuming one device replaces the other.
Keep buying and compatibility claims separate. This guide does not add a Bambu product to the site's verified Amazon catalog and does not imply that an AMS-specific accessory works with every revision. Verify the manufacturer page, delivered manual, regional power parts, printer compatibility, spool fit, and current firmware for the exact system.
Run one supported cycle and hand the spool back to storage
Start with one identified spool and one supported procedure. Confirm the lid, vent, reel rotation, feed path, and power arrangement by the matching instructions. During the cycle, observe the supported interface without opening, bypassing, or modifying the system. Stop when the exact manual reports a fault, when the reel binds or deforms, or when the documented process cannot be maintained.
After the cycle, compare one repeatable print while keeping other settings stable. A chamber humidity reading describes air near its sensor, not residual moisture through the spool. Return unused material to the system's supported airtight mode or another suitable sealed container, service desiccant by its exact instructions, and record where the spool went.
Sources and research notes
This guide synthesizes published guidance. It does not describe our own laboratory or hands-on product testing. AMS, AMS lite, AMS 2 Pro, and AMS HT are separate systems; model, printer, power, temperature, capacity, material, and feeding statements apply only where the linked Bambu source documents them.