Calculation Example - Conel CLEAR Serie Montage- Und Betriebsanleitung

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If the required mixed water hardness has still not been reached, it can be adjusted by turning the setting
screw of the blending valve using a coin by not more than half a turn within the marked adjustment range.
Recommended hardness is approx. 8 °dH.
The setting may have to be changed and remeasured several times before the required value is reached.
The softening increases the sodium concentration in the mixed water, depending on the raw water hard-
ness and the mixed water hardness set.
In Germany in accordance with the current drinking water regulations the limit value for sodium in drink-
ing water is 200 mg/l. This does not apply to mineral and table water. Their limit values are considerably
higher, some have values above 1000 mg of sodium per litre. Values may vary in other countries, please
consult your local regulations.
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 the mixed water hardness accordingly.
The sodium content must be recalculated.
Fig. 10: Setting the blending