STIEBEL ELTRON Heat pumps, Technical Manual

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Cooling with a geothermal probe
Geothermal probes are sized in accordance with the heat pump heating output.
the heat that must be transferred to the ground during passive cooling is approx. 70% of the extraction rate (approx.
35 w/m probe length).
Example:
Heat pump wPF/C 10 cool
required geothermal probe 2 pce. @ 70 metre length
extraction rate approx. 55 w per metre equates to approx. 7.7 kw.
the transfer to the ground amounts to approx. 5.4 kw.
Cooling with groundwater
the amount of groundwater that can be utilised to remove heat is determined in accordance with the amount of
groundwater required by the heat pump.
the temperature differential between the groundwater and the cooling water is approx. 5 K.
Example:
Heat pump wPw 13
required volume of groundwater 2.6 m³/h
the groundwater can remove approx. 15.1 kw.
Sizing table geothermal probe DN 25
for normal solid rock, extraction capacity 55 w/m (average value)
Heat pump type
source temperature 0 °C
Flow temperature 35 °C Geothermal probe
32 x 2.9
number Geothermal probe
32 x 2.9
Depth extraction,
heating mode transfer, cooling
mode
Heating output Cooling capacity
wPF/C 5 cool 5.8 kw 4.5 kw 1 pce. 82 m 4.5 kw 3.2 kw
wPF/C 7 cool 7.8 kw 6.0 kw 1 pce. 109 m 6.0 kw 4.2 kw
wPF/C 10 cool 9.9 kw 7.7 kw 2 pce. 70 m 7.7 kw 5.4 kw
wPF/C 13 cool 13.4 kw 10.3 kw 2 pce. 94 m 10.3 kw 7.2 kw
wPF 16 cool 16.1 kw 12.5 kw 3 pce. 84 m 13.8 kw 9.6 kw
Sizing table groundwater
Groundwater temperature approx. 15 °C (average value during cooling operation)
Heat pump type
source temperature 10°C
Flow temperature 35°C
Groundwater amount transfer, cooling mode
Heating output Cooling capacity
wPw 7 7.2 kw 5.9 kw 1.5 m³/h 8.7 kw
wPw 10 10.0 kw 8.2 kw 2.1 m³/h 12.2 kw
wPw 13 12.5 kw 10.2 kw 2.6 m³/h 15.1 kw
wPw 18 17.1 kw 14.1 kw 3.4 m³/h 19.7 kw
wPw 22 M 21.7 kw 18.2 kw 4.4 m³/h 25.5 kw
coolIng capacIty