5.3 Freshwater requirements

Only clean, clear water with values in accordance with those in the following table must be used for preparing the coolant. If the limit values for the water are exceeded, hardness or mineral content can be decreased by adding demineralized water.

For preparation of coolant without antifreeze protection:

Item Total earth alkalines1) (Water hardness) pH value at 20 °C Chloride ions Sulfate ions Total chloride + sulfate ions Bacteria Fungi, yeasts Minimum 0 mmol/l 0°d 5.5

are not permitted! Maximum 2.7 mmol/l 15°d 8.0 100 mg/l 100 mg/l 200 mg/l 103CFU (colony forming unit )/ml

Table 13:

1) = Common designations for water hardness in various countries: 1 mmol/l = 5.6°d = 100 mg/kg CaCO³ • 1°d = 17.9 mg/kg CaCO³, USA hardness • 1°d = 1.79° French hardness • 1°d = 1.25° English hardness

For preparation of emulsifiable corrosion inhibitors:

Item Total earth alkalines1) (Water hardness) pH value at 20 °C Chloride ions Sulfate ions Total chloride + sulfate ions Bacteria Fungi, yeasts Minimum 0.36 mmol/l 2°d 7.0

are not permitted!

Table 14:

1) = Common designations for water hardness in various countries: 1 mmol/l = 5.6°d = 100 mg/kg CaCO³ • 1°d = 17.9 mg/kg CaCO³, USA hardness • 1°d = 1.79° French hardness • 1°d = 1.25° English hardness

If the water is too soft, this can result in foam formation and the water has to be hardened before application by adding hard water. If the water is too hard, this impairs the emulsion stability. This causes increased oil separation and the formation of deposits in the system. Excessively hard water must therefore be softened by blending with soft water. Maximum 1.8 mmol/l 10°d 8.0 100 mg/l 100 mg/l 200 mg/l 103CFU (colony forming unit )/ml