Hitachi 7E300020, Технический каталог, Страница: 112 / 158

9. Refrigerant and water piping
TCGB0075 rev.0 - 11/2012
112
9.3.3 Water quality
C A U T I O N
• Water quality must be according to EU council directive 98/83 EC.
• Water should be subjected to filtration or to a softening treatment with chemicals before application as treated
water.
• It is also necessary to analyse the quality of water by checking pH, electrical conductivity, ammonia ion con-
tent, sulphur content, and others. Should the results of the analysis be not good, the use of industrial water
would be recommended for the heating coil circuit.
• It is mandatory to do not add any kind of antifreeze product to the water circuit.
•
To avoid deposits of scale on the heating coil surface it is mandatory to ensure a high water quality with low
levels of CaCO
3
.
The following is the recommended standard water quality.
Item
DHW space Tendency
(1)
Water supplied
(3)
Corrosion
Deposits of
scales
Electrical Conductivity (mS/m) (25°C)
{µS/cm} (25 °C)
(2)
100~2000
Chlorine Ion (mg CI¯/I) max. 250
Sulphate (mg/l) max. 250
Combination of chloride and sulphate (mg/l) max. 300
Total Hardness (mg CaCO
3
/I) 60~150
N O T E
• (1): The mark “ ” in the table means the factor concerned with the tendency of corrosion or deposits of scales.
• (2): The value showed in “
{}
” are for reference only according to the former unit.
• (3): Water range will be according s/UNE 112076:2004 IN.