What should I do before using the WDU28 for the first time?

Before washing for the first time, you must run the Drum Clean programme without laundry to remove residual test water. First, insert the mains plug, turn on the water tap, press the power button, close the door, select Drum Clean 90°C, open the detergent drawer, pour approximately 1 litre of water into dispenser II, add standard detergent according to manufacturer's instructions (using only half the recommended amount to prevent over-sudsing), close the drawer, and start the programme. (Page 20)