Herz OXFORD, Installation, Maintenance & Operating Instructions

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Page 14
5.1.4 Water quality
Parameters Recommended limits for water quality
PH value 7 - 9
Alkalinity 60 mg/l < [HCO
3
-
] <300 mg/l
Electrical conductivity <500 µS/cm
Hardness [Ca
2
+,Mg
2
+]/[HCO
3
-] > 0.5
Chloride
1000 mg/l at 25 °C
300 mg/l at 50 °C
100 mg/l at 80 °C
0 mg/l at T > 100 °C
Sulphate [SO
4
2-
] < 100 mg/l and [HCO
3
-
]/[SO
4
2-
] >1
Nitrate [NO
3
-
] < 100 mg/l
Free chlorine < 0.5 mg/l
Note: The given reference values for the heat exchanger are dependent on the required water quality.
Consideration should be given to the use of a scale prevention device when aggressive water supplies are
present
No Description Part No Insert Seals Part No Qty
1 DHW Heat Exchanger 1401847 1402045 4
2 Pressure Temperature Control valve 1400800 1 1402047 2 of each
3 Thermostatic Head with contact sensor 1401965
3 Contact Sensor connection sealing nut 1401898
4 Strainer mesh 1401897
5 Primary Circulation Bypass Valve 1774691 1639091 1 1300101 2 of each
6 Return Temperature Limiter 1920102
7 Differential Pressure Control Valve 1400259 1402045 2
8 Optional Heat Meter 1402267 1402045 2
8 Heat meter probe connection nut 1402055
9 Drain Valve (red handle) 1027609
10 Drain Valve (green handle) 2027609
11 15 l/min Flow limiter 1402069
11 20 l/min Flow limiter 1402057
12 Manual Air Vent 1402059
13 Drain Valve (Red test point) 1028422
14 Drain Valve (Blue test point) 1028421
Seals
Part No
Flat Sealing gaskets standard 1402045
Flat Sealing gaskets for PTC 2mm 1402046
Flat Sealing gaskets for PTC 3.4mm 1402047
Euro cone to flat sealing nipple 1300101