eta Fresh water module 33, Руководство по эксплуатации

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Information on cold water Thresholds
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cannot be ruled out depending on other water
properties. At a conductance of over 1000 μS/cm
corrosion is likely.
Therefore, the rule of thumb results in the following
thresholds for copper-soldered heat exchangers in
regard to water hardness:
If the water hardness is minimised by a
softening system, the electrical conductivity
of the drinking water still remains unchanged.
8.4 Thresholds
Thresholds for the water quality on the drinking water side
Tab. 8-1: Thresholds for drinking water
Conductance Water hardness Resistance
< 500 μS/cm
at approx.
<14.3° dH corrosion-
resistant
500-1000 μS/cm
at approx. 14.3 -
28.6° dH
Corrosion is no
excluded
> 1000 μS/cm
approx. >28.6°
dH
Corrosion is
likely
Conductance Water hardness Resistance
Substance
Standard heat exchanger
(soldered with copper solder)
"INOX" heat exchanger (soldered
with stainless steel brazing
solder)
Appearance clear clear
Odour odourless odourless
Impurities free from deposits and/or particles free from deposits and/or particles
pH value between 7.5 and 8.5 between 6 and 10
electrical conductivity < 500 µS/cm no restriction
Chloride (Cl-) < 100 mg/l < 100 mg/l
Sulphate (SO
4
2-
) < 100 mg/l no restriction
Nitrate (NO
3
) < 100 mg/l no restriction
Nitrite (NO
2
) not permitted not permitted
Ammonia (NH
3
, NH
4
+
) < 2.0 mg/l no restriction
Free chlorine (Cl) < 1.0 mg/l < 1.0 mg/l
Iron (Fe) < 0.2 mg/l no restriction
Aluminium (Al) < 0.2 mg/l no restriction
Manganese (Mn) < 0.1 mg/l no restriction
Free carbon dioxide (CO
2
) < 5 mg/l no restriction
Hydrogen sulphide (H
2
S) < 0.05 mg/l no restriction
Hydrogen carbonate (HCO
3
) < 300 mg/l no restriction