Smeg DF410BL - Manual (Page 11)

User instructions
SWITCH SETTING
The dishwasher is equipped with an device for the user to adjust the
water softening system according to the hardness of the water supply.
The setting switch is inside the plastic locking ring located on the right-
hand side, inside the dishwasher.
WATER HARDNESS TABLE
WATER HARDNESS
German Degrees (°dH) French Degrees (°dF)
SETTING
0 - 4 0 - 7 Setting N. 1 NO SALT
5 - 15 8 - 25 Setting N. 1
16 - 23 26 - 40 Setting N. 2
24 - 31 41 - 60 Setting N. 3
32 - 47 61 - 80 Setting N. 4
48 - 58 81 - 100 Setting N. 5
Contact your local water board for information on the hardness of your
water supply.