Open the Device by following these steps:

Open the device only with the power supply plug disconnected.

Place the device on a non-slip surface with the top facing downwards.

Remove the filter cassette from the top part of the housing

Undo and remove the 6 screws (34)

Open the bottom part of the housing (35) away to the side.

Undo the connecting cables for the humidifier (42) and the alarm (43)

You can now put the bottom part of the housing (35) to one side.