37
Water connections
6.1.2 Water characteristics
Circulators are designed to operate optimally only with clean, good quality mains water and may be aected
by the presence of oxygen, limescale, sludge, abnormal acidity levels and other substances (including
chlorides and minerals). The same can be said for the plate heat exchanger.
Excessive water hardness can create deposits and limescale build-up that can damage the unit. The
presence of critical concentrations of other components in the circuit can trigger corrosive processes or
other quality problems in the circulator and plate heat exchanger. Check that the system water complies with
the concentration limits given in the table.
W
CAUTION
If the water hardness is too high, assemble a water softener to reduce the value.
W
CAUTION
The heating system must be airtight and materials must be chosen that are not sensitive to oxygen diusion
(which can cause corrosion).
Characteristics Water component for corrosion limit on Copper
pH (25°C) 7.5 to 9.0
SO4
--
< 100
HCO3
-
/ SO4-- > 1
Total Hardness 8 to 15 °f (4.5-8.5 dH)
Cl- < 50 ppm
PO4
3-
< 2.0 ppm
NH3 < 0.5 ppm
Free Chlorine < 0.5 ppm
Fe3
+
< 0.5 ppm
Mn
++
< 0.05 ppm
CO2 < 50 ppm
H2S < 50 ppm
Temperature < 65 °C
Oxygen content < 0.1 ppm
Sand 10 mg/L 0.1 to 0.7mm max diameter
Ferrite hydroxide Fe3O4 (black) Dose < 7.5 mg/L 50% of mass with diameter < 10 µm
Iron oxide Fe2O3 (red) Dose < 7.5mg/L - Diameter < 1 µm
To Next Page
Loading...
Need help?
General