That's how the washing machine lives longer
The heater of my washing machine was totally calcified, although we have here actually soft water. My husband removed it because the machine did not heat up and brought it to the professional to buy a new heater.
This gave the following advice: In the present time, many people only wash at low temperatures. At most 60 degrees! But that is not enough to completely dissolve the washing powder and so every time puts a fine film around the heating element and after a few years, he is so closed that he can not heat.
In between you should wash the laundry at 90 degrees and add vinegar from time to time. This would cause the detergent residue to dissolve better and keep the washing machine longer. You do not need expensive additives (Calg ..) to extend the life of the washing machine. I now follow the advice of the professional and wash 1-2 times a month at 90 degrees.
