STIEBEL ELTRON Heat pumps, Техническое руководство

Страница: 40 / 260

40 www.stiebel-eltron.CoM
coolIng wItH tHE HEat pUmp SyStEm
Passive cooling
with passive cooling, the low
temperature of the groundwater
or that of the upper earth crust is
transferred to the heating system via
a heat exchanger. the heat pump
compressor will not be started, i.e. the
heat pump remains passive.
Active cooling
During active cooling, the cooling
output of the heat pump (cold side) is
transferred to the heating system. the
heat pump compressor will be started,
i.e. the heat pump becomes active.
Procedure for allowing passive
cooling:

Calculating the cooling load
– to VDi 2078
– in accordance with a standard
form
– in accordance with the m² area
of the living space (factor)
 Determining the cooling capacity
of the heat sink
– geothermal probe
– groundwater
 sizing the distribution system
– underfloor heating system
– fan convectors

Heat pump installation
– wPC cool
– wPF
Design information:
the cooling capacity of the heat sink
can be seen in the table on page 41.
For example, two geothermal probes
with a depth of 94 metres can transfer
approx. 7.2 kw to the ground (wPC 13
cool).
the heat transfer by the heat sink
must not exceed the cooling load
of the building. the required room
temperature cannot be achieved if the
cooling load is greater. if necessary,
some rooms must be excluded from
the cooling demand to achieve the
required room temperature in the
other rooms.
Average temperatures underground (°C)
Drilling depth (m) exposed site Urban area High location
0 9.5 9.5 3.2
25 11.3 12.5 8.0
50 12.0 13.5 8.7
75 12.8 14.5 9.5
100 13.5 15.5 10.2
125 14.3 16.5 11.0
150 15.0 17.5 11.7
175 15.8 18.5 12.5
200 16.5 19.5 13.2
Temperature curve underground
Cooling of buildings
Disabled enabled
Passive systems Active systems
 Utilisation of natural heat sinks

Cool ground / cool night air

Utilisation of storage effects
 Utilisation of refrigerators
*+1 °C temperature rise every 33 m
Dep
th (m)