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© STULZ GmbH – all rights reserved EN/06.2021/G23
minispace cw original instructions
Cooling water quality
noTICe
Observe the following limits for the water circuit of the A/C unit.
Water properties and ingredients
Carbonate hardness
°dH
<4
Carbonate hardness when adding inhibitors
°dH
<20
Total hardness
°dH
<15
pH value
7.0 - 9.0
pH value with light metal*
7.0 - 7.5
Chloride content
mg/l
<100
Chloride content with austenitic steels
mg/l
<50
Free chlorine
mg/l
<0.05
Hydrogen sulphide
mg/l
<0.05
Ammonia (NH
3
/NH
4
+
)
mg/l
<0.05
Sulphate
mg/l
<100
Manganese
mg/l
<0.05
Iron
mg/l
<0,2
Sulphide
mg/l
<0.05
Free aggressive carbonic acid
mg/l
<15
Suspended solids
mg/l
<20
Number of germs
cfu/ml
<1000
Electric conductivity without inhibitors
µS/cm
10 - 500
Electric conductivity with inhibitors
µS/cm
<2200
cfu - colony forming units
*aluminium or titanium.
All data refer exclusively to the A/C unit.
noTICe
• Check the water quality regularly.