Coffee powder is ejected dry

Hello Forum,

I have for several years a JURA Impressa C5. After I had some time ago again and again problems that coffee powder and water landed separately in container or I have treated me revised brewing unit and now recently installed. Initially, it was still ok, although coffee came out much slower and also with less water.
Then, only every second or third reference has led to the coffee, mostly coffee was ground, but then the powder has immediately fallen into containers without water was drawn. Rather steam generator has blinked. After operating, steam let out and turn back the adjustment knob, however, has not changed the situation.
Have removed brewing unit again and checked drain valve manually, can be moved easily in contrast to the old brewing unit.

PS: Error has occurred virtually with installation of the new brewing unit, although here at least initially still came some coffee.
By the way, during the rinsing process also no water comes, from the steam generator already.

Does anyone know error picture or has idea how error can be searched?

Mechan. Knowledge: yes Electr. knowledge: yes

Check the drain valve. It could be defective. Do you have lime water? If so, decalcify thoroughly. Best with descaler based on amidosulfonic acid.
If you use a water filter, remove it beforehand and program it so that you can decalcify.

Okay, thanks. For suggestion. Will decalcify tonight.

@ Schlawi

...why wander off into the distance...
Well, you were right of course, just decalcify properly and the machine runs like the first day. It's soo easy if you go about it the right way.

Thanks again for the tip. Here's a star for the Christmas tree.