Lauda MC 250, Руководство по эксплуатации, Страница: 28 / 72

There are specific requirements for the cooling water concerning
its purity. In accordance with the cooling water requirements, a
suitable process for treatment and maintenance of the water must
be used. The condenser and the complete cooling water circuit can
be clogged, damaged and leak due to unsuitable cooling water.
Extensive consequential damage to the complete refrigerant circuit
can occur. The cooling water quality is dependent on the local con-
ditions.
 Free chlorine, e.g. from disinfectants and water containing
chloride results in pitting corrosion in the cooling water circuit.
 Distilled, deionised or demineralised water is not suitable due
to its corrosive properties and results in corrosion in the cooling
water circuit.
 Seawater is not suitable due to its corrosive properties and
results in corrosion in the cooling water circuit.
 Water containing iron and iron particles in the water result in
rust formation in the cooling water circuit.
 Hard water is not suitable for cooling due to the high lime con-
tent and results in calcification in the cooling water circuit.

Cooling water with suspended matter is not suitable.
 Untreated, not purified water, e.g. river or cooling tower water
is not suitable due to its microbiological content (bacteria)
which can settle in the cooling water circuit.
Data Value Unit
pH value 7.5 – 9.0
Sulphates [SO
4
2- ]
< 70 mg/l
Hydrogen carbonate [HCO
3
- ] / Sul-
phates [SO
4
2-
]
> 1.0
Water hardness (alkaline earth ions
content)
0.71 - 1.52 mmol/l
Hydrogen carbonate [HCO
3
- ]
70 – 300 mg/l
Conductivity 10 - 500 μs/cm
Chlorides (Cl - )
< 50 mg/l
Sulphite (SO
3
2-
)
< 1 mg/l
Free chlorine gas (Cl
2
) < 1 mg/l
Nitrates (NO
3
-
)
< 100 mg/l
Ammonia (NH
3
) < 2 mg/l
Iron (Fe), dissolved < 0.2 mg/l
Manganese (Mn), dissolved < 0.1 mg/l
Aluminium (Al), dissolved < 0.2 mg/l
Free, aggressive carbonic acid (CO
2
) < 5 mg/l
General requirements
Suitable cooling water quality
Before commissioning
Microcool 28