Conel CLEAR SOFT TWIN, Operating Instructions Manual

Page: 72 / 140

72
Calculating the sodium content
°dH raw water hardness (ask the waterworks or measure with a hardness test device)
− °dH mixed water hardness (measured value)
= °dH difference of water hardness
× 8,2 mg Na
+
/liter × °dH exchange value for sodium ions
= mg/l increase in sodium content due to softening
+ mg/l sodium already in the raw water (ask the waterworks)
= mg/l total sodium content in mixed water
Calculation example
20 °dH raw water hardness
− 8 °dH mixed water hardness
= 12 °dH difference of water hardness
× 8,2
= 98 mg/l due to softening
+ 10 mg/l from waterworks
= 108 mg/l total sodium content
If the calculated overall sodium concentration exceeds the value of 200 mg/l which is permitted by local
drinking-water regulations, it can be corrected by increasing residual hardness.
Based on raw water hardness and the residual water setting, the electronics unit checks the sodium con-
centration resulting from these values. The raw water sodium concentration will not be considered in the
calculation performed by the electronics unit. Upon exceeding a limit value stipulated by local drinking-wa-
ter regulations, the display first indicates:
to be followed after 3 seconds with the message:
After 3 seconds, the admissible minimum value for residual hardness is shown on the display, e.g.:
After another 3 seconds, the following comes up:
By pressing <OK>, the minimum allowable residual hardness value is set. By pressing

and

the de-
sired residual hardness can be set and enforced by pressing <OK> despite exceeding the sodium limit.
Attention!
Na.concentration
see instruction
manual
min. permissible
res. hard. 10 °dH
Accept <OK>
or setting
The exceeding of the sodium limit value is indicated by a small “2” at the end of the
first line of the display.