Hello, the duct where the hot water passes to fall on the coffee can be covered with water scale, you can do a cleaning by placing in the water tank a well of white vinegar or the one you have in your house and fill a little more half of the tank with drinking water and you run the coffee maker in a normal way to prepare coffee only without coffee when the liquid is passing this anger by loosening the impurities that will remain in the jar together also that you will see that more water comes out again does this About two or three times by changing the vinegar and the water when you recover the normal flow of water, you just have to fill the entire tank with water and rinse three or four times until the water greets with vinegar.