SUNLU AMS Heater: problems, parts and running costs

Checked: 2026-10-14

Summary

The SUNLU AMS Heater adds active drying to a first-generation Bambu Lab AMS, but owners report fan noise, PLA spool deformation and kinking under sustained heat, cardboard roll contraction, desiccant jars unscrewing, an oversized hex key, and one case of AMS damage above 40 degrees C. Running cost is small: electricity at 220 W while it runs plus desiccant. It is strong value at or below about $100 for AMS Gen 1 owners, reasonable from $101 to $120, and weak above $120.

Common problems and fixes

Fan noise — owners’ experience varies: one reported two units “sounded terrible” at first, another compared a single unit to a small, quiet air purifier. Place it where noise is tolerable; no dBA measurement exists. [7][15]
PLA spool deformation — sustained heat can deform PLA spool adapters; community advice is to replace PLA components with PETG. [8]
PLA filament kinking — heat can kink PLA at the feeding funnel; rotating rolls is recommended. [8]
Cardboard rolls contract — cardboard spools can contract and shed adapters under heat. [8]
Desiccant jars unscrew — intermittent temperature changes can loosen them. Check and retighten periodically. [8]
Oversized hex key — the included hex key may not fit the screws without modification. Use your own correctly sized tool. [8]
AMS damage above 40 degrees C — one owner reported damaging an AMS by running the heater above 40 degrees C. Keep temperatures conservative until more data exists. [9]
No handle, poor visibility — there is no groove for lifting, and filament levels cannot be seen from above without lifting the lid. [4]
No independent lab data — heat-up time, temperature uniformity and fan noise are not independently measured; all caveats above are owner experience. [4]

Parts and consumables

Yearly running cost

Not enough data for a yearly dollar figure. Recurring costs are electricity at 220 W while the heater runs and desiccant for AMS maintenance. [1][8]

When it is a good buy

At or below about $100 it is strong value for an AMS Gen 1 owner who wants active drying without replacing the whole unit. From $101 to $120 it is still reasonable for AMS Gen 1 compatibility and simultaneous drying. Above $120 the money is better saved toward the Bambu Lab AMS 2 Pro or a standalone dryer. [3][4] Price history from the sources: the SUNLU US store listed it at $101.99 on 2026-10-14 [10]; Creative Bloq saw an early-bird price of $109.99 and a regular $119.99 in August 2025 [3]; The Gadgeteer saw $119.99 regular and $109.99 on sale in July 2025 [4]. Compatibility is AMS Gen 1 only; AMS 2 and AMS Lite are not supported, and the AMS Lite Heater is a separate product for the A1, A1 Mini and A2L. [1][5] Warranty is 12 months from purchase, and the unit is sealed with no documented user-serviceable parts. [14]