Remove the water tank, fill it with fresh water and refit it securely. Ensure the tank is sitting correctly in its housing. If the machine displays a water tank warning despite the tank being full, remove and reseat it before attempting another drink.

If a water filter is fitted, check that it has been installed correctly. An incorrectly fitted or restricted filter may affect water delivery. Follow the machine's water filter removal and installation procedure when checking the filter, and use the machine's settings to register any filter changes.

Air can enter the water circuit after the tank has emptied or following maintenance. If the machine requests venting or prompts you to follow a water system procedure, complete the instructions shown on the display. Do not repeatedly operate the pump if water is not flowing.

Place a suitable container beneath the hot water outlet and select the hot water function. If hot water dispenses normally but coffee does not, the problem may be limited to coffee preparation rather than the entire water supply. If no water flows, stop the test and check for any display messages.

Switch off the machine and allow it to cool. Remove the brewing unit using the access panel and locking handle, following the manual. Rinse it thoroughly under running water, paying attention to coffee residue around the filter surfaces. Allow excess water to drain, then refit and lock the brewing unit securely. Melitta specifically recommends this check when coffee fails to flow.

Limescale can restrict water flow through the machine. If water is dispensing slowly or the appliance is overdue for descaling, open the Settings menu using the rotary switch and select Care > Descaling. Follow the instructions displayed, using a suitable Melitta descaler. If no water flows at all and the programme cannot operate, seek professional support rather than repeatedly running the pump.