Melitta Coffee Machine Calc Button 4. Coffee Maker Not Heating: One more problem that could arise in Melitta coffee makers is when the machine won't warmth the drinking water effectively. This may be resulting from a concern with the heating element or an issue with the ability supply. A: https://melitta-coffee-machine.kylieblog.com/36483259/melitta-filter-coffee-machine-what-does-melitta-coffee-machine-manual-mean