How to Fix / Troubleshooting

Safety: Allow the oven to cool completely; do not force the door open. Disconnect power.

Steps:

Once cool, many Bomann models will automatically release the door lock. If not, consult the manual for the emergency release procedure (often via a lever accessible behind the control panel or through the door latch area).
Check the cooling fan and ventilation for proper operation as pyrolysis generates very high temperatures.
Test the high-temperature thermostat and NTC sensor for continuity and correct resistance.
Replace any failed safety thermostat or sensor before attempting another pyrolytic cycle.
If E20 recurs, the main control board may be mismanaging the pyrolytic cycle and should be evaluated by a technician.

Oven shows E20 and pyrolytic cleaning stops with door locked

Possible Causes