STIEBEL ELTRON WPF 5 basic - Page 68

INSTALLATION
Specication
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WPF 5 basic WPF 7 basic WPF 10 basic WPF 13 basic WPF 16 basic
Water quality requirements
Water hardness °dH ≤3 ≤3 ≤3 ≤3 ≤3
pH value (with aluminium fittings) 8.0-8.5 8.0-8.5 8.0-8.5 8.0-8.5 8.0-8.5
pH value (without aluminium fittings) 8.0-10.0 8.0-10.0 8.0-10.0 8.0-10.0 8.0-10.0
Chloride mg/l <30 <30 <30 <30 <30
Conductivity (softening) μS/cm <1000 <1000 <1000 <1000 <1000
Conductivity (desalination) μS/cm 20-100 20-100 20-100 20-100 20-100
Oxygen 8-12 weeks after filling (desalination) mg/l <0.1 <0.1 <0.1 <0.1 <0.1
Oxygen 8-12 weeks after filling (softening) mg/l <0.02 <0.02 <0.02 <0.02 <0.02
Heat transfer medium requirements on the heat source side
Ethylene glycol concentration, geothermal probe Vol.-% 25 25 25 25 25
Ethylene glycol concentration, geothermal collector Vol.-% 33 33 33 33 33
Values
Nominal design heating system flow rate at B0/W35 and 7K m³/h 0.71 0.91 1.22 1.58 2.08
Min. heating flow rate m³/h 0.5 0.64 0.86 1.1 1.45
Heating flow rate (EN 14511) for A7/W35, B0/W35 and 5 k m³/h 0.99 1.27 1.71 2.21 2.91
Flow rate on heat source side m³/h 1.4 1.9 2.2 3.1 3.8
Internal volume on the heating side l 2.4 2.8 3.4 3.4 3.4
Internal volume on the source side l 2.9 3.5 4.1 4.1 4.1
Available external pressure differential, heating system hPa 350 350 260 167 63
Pressure differential on the heat source side hPa 100 110 120 230 340