1. Hard water is prone to lime precipitation. Lime deposits in the pipes lead to deposits and biofilms.
2. Lime deposits can reduce the service life of the heater.
3. Hard water leads to strongly increasing pH values which can only be lowered with a lot of pH-minus. The constant lowering of the pH-value costs a lot of time and is expensive.
4. Hard water with a high pH value can lead to clouding of the water.
5. Hard water reduces the effectiveness of water care products. 

Ask your water supplier. He knows the hardness of your water.Let them give you the total hardness in degrees of english hardness.

Or:

You can determine the water hardness yourself with our Water Hardness Test Set.

To the Hardness Test Set