Bosch Dryer Error Codes
Bosch ventless heat-pump dryers use F-codes for condenser, heat pump, and moisture sensor faults distinct from vented American dryers.
General troubleshooting
Try these checks before opening a specific error code page—they resolve many Bosch dryer faults without parts.
- 1Clean the lint filter and the condenser drawer per the manual schedule
- 2Empty the condensed water reservoir if not plumbed to a drain
- 3Avoid overloading—Bosch compact drums need room for heat-pump airflow
- 4Run a high-heat timed cycle to test heat pump separately from sensor dry
- 5Verify the room temperature is above 50°F for heat-pump efficiency
Common symptoms
Owners often search for a code after noticing one of these issues on their Bosch dryer:
- Long dry times on heat-pump models WTG86400UC
- Condenser unit needs cleaning message or poor drying performance
- Door won't lock and cycle won't start
- Heat pump not warming the drum on eco cycles
- Lint buildup in the condenser chamber reducing airflow
All Bosch dryer error codes
| Code | What it means | Guide |
|---|---|---|
| E01 | Lint filter airflow sensor blockedE01 is Bosch's early airflow warning—the lint filter sensor detects restricted exhaust before critical overheating. Heat-pump models like the WTG86400 series will continue running but drying times stretch and the display holds E01 until airflow improves. | View fix → |
| E03 | Condensation drain hose blocked or kinkedE03 on Bosch condenser and heat-pump dryers means the condensation drainage hose is blocked, kinked, or installed too high. Water that should leave the condenser backs up and triggers E03—distinct from lint-related E01. | View fix → |
| E05 | Main control board relay faultE05 is grouped with Bosch electronic fault codes indicating a relay or driver failure on the main control board. The drum may not start, heat may not engage, or the display may flash E05 at power-up after a surge. | View fix → |
| E06 | Heating element circuit failureE06 on older Bosch dryer firmware indicates heating element failure—the drum tumbles but exhaust air stays cool and the cycle runs without drying. Newer models often show E63 for the same fault; troubleshooting is identical. | View fix → |
| E07 | Moisture sensor signal invalidE07 reports a fault in the moisture sensing circuit—the two curved metal strips inside the drum opening did not send valid conductivity readings. Auto-dry programs stop early or refuse to start because the board cannot judge remaining dampness. | View fix → |
| E08 | Electronic control fault on heat circuitE08 is among Bosch dryer electronic fault codes tied to heat regulation electronics. The display may show E08 at cycle start or mid-dry when the board detects an invalid heat circuit signal—often after E01 or E12 airflow warnings were ignored. | View fix → |
| E09 | Heat pump or element regulation faultE09 on Bosch heat-pump dryers indicates an electronic fault in the heat regulation path—grouped with E06 and E08 on the official chart. Heat output stops even though the drum may continue tumbling on some firmware versions. | View fix → |
| E10 | Drum drive motor not reaching speedE10 indicates the drum motor did not reach operating speed after start—the belt, motor, or motor capacitor failed to turn the drum at the expected RPM. You may hear a hum with no rotation, or the drum moves briefly then stops with E10. | View fix → |
| E12 | Heat pump overheating from limescale or blocked airflowE12 on Bosch heat-pump dryers signals overheating—official guidance cites limescale buildup in the heat pump when airflow was already restricted. The dryer shuts down to protect the sealed refrigeration circuit and heating components. | View fix → |
| E14 | Ambient room temperature too low to runE14 means ambient temperature is outside the operating window—heat-pump Bosch dryers often require roughly 41°F (5°C) minimum at the installation location. Cold garages and unheated mudrooms trigger E14 at startup because the heat pump cannot extract moisture efficiently. | View fix → |
| E15 | Condensate collection tank fullE15 on Bosch condenser dryers with a removable tank means the condensate reservoir is full—the machine stops to prevent overflow. On plumbed installs, E15 can also appear when condensate cannot reach the drain despite an empty tank symbol. | View fix → |
| E16 | Door opened during an active cycleE16 is informational—the door switch opened while the dryer was running. Bosch stops the drum and heat as a safety measure. The code clears when you close the door and restart; it is not a hardware failure unless E16 appears without anyone opening the door. | View fix → |
| E17 | Maximum drying time reached without finishE17 appears when Bosch's built-in maximum drying duration—about four hours on many models—is reached without the moisture sensor detecting dry clothes. Clothes remain damp and the cycle terminates with E17 to prevent endless run time. | View fix → |
| E18 | Condensate pump or drain path blockedE18 signals condensate removal failure—water from the heat exchanger cannot exit through the drain hose or internal pump. Distinct from E03 kink faults, E18 often means a clog or failed pump on plumbed heat-pump dryers. | View fix → |
| E19 | Control board communication errorE19 means internal communication failure between the user interface board and the power or heat-pump control module. The display may freeze, cycles may cancel randomly, or E19 appears at power-up after electrical disturbance. | View fix → |
15 codes documented with causes, fixes, and affected models.