5.3.3 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 content, sulphur content, and others. Should
the results of the analysis be not good, the use of industrial water would be recommended.
• No antifreeze agent shall be added to the water circuit.
• To avoid deposits of scale on the heat exchangers surface it is mandatory to ensure a high water quality with low levels of CaCO
3
.
Recommendations for the DHW circuit
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 shown in “{}” are for reference only according to the former unit.
• (3): Water range will be according s/UNE 112076:2004 IN.
5.3.4
Water flow control
YUTAKI pumps can estimate the water flow by electronic calculation. Therefore, there is no need to install a water flow switch with
the new YUTAKI pumps.
However, if a secondary pump is installed or glycol is used, it is necessary to install a water flow control, as the electronic calculation
may be affected.
REFRIGERANT AND WATER PIPING
PMML0575 rev.1 - 09/2021
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