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Hint!
If you fail to adhere to the limiting val-
ues stated in VDI 3803, the manufac-
turer cannot provide any warranty for
water carrying parts within its supplied
components.
Clarification as to whether or not it is
possible to adhere to these limiting
values with the respective water condi-
tions should be agreed on with a spe-
cialist company during the planning
and design phase.
The limiting values as per VDI 3803, as required for
the use of carbon steel components in non corrosive
water systems, are listed below.
Water quality requirements, parameters
Criterion Value Unit
Appearance clear, with-
out sedi-
ment
Colour colourless
Odour none
pH level at 20 °C 7.5 - 9.0
Electrical conductiv-
ity
LF < 220 mS/m
Soil alkali
Ca
2+
,
Mg
2+
< 0.5 mol/m³
General hardness,
for stabilization
GH < 20 °d
Carbonate hard-
ness without hard-
ness stabilizer
KH < 4 °d
Chloride Cl < 150 g/m³
Sulphur
SO
4
< 325 g/m³
Water quality requirements, parameters
Criterion Value Unit
Active biological
components
KBE < 10,000 per ml
Thickness factor EZ 2 - 4
The use of carbon steel and cast iron is required in
the most of applications water conditioning with cor-
rosion inhibitors.
The use of stainless steel requires very special moni-
toring of water in apply to Chloride contents (risk of
stress crack and pitting corrosion).
Hint!
Recommend when using plate heat
exchangers in the refrigerant circuit
< 100 ppm Cl while using steel 1.4301
and
maximum 40°C wall temperature in the
plate heat exchanger
< 200 ppm Cl while using steel 1.4401
and
maximum 100 °C wall temperature in
the plate heat exchanger
fig.28: Corrosion resistance in presence of chlorides
X
Chloride ion concentration in ppm Cl
-
Y Wall temperature heat exchanger in °C
A AISI 304
B AISI 316
C SMO 254
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages Description of Design and Function
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015 51