Bosch Geothermal Heat Pumps, Руководство по применению

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4 6 | Bosch Geothermal Heat Pumps
Bosch Thermotechnology Corp. Data subject to change
Applications Manual
7 Closed-Loop Geothermal Heat
Pump Systems
Closed-loop ground heat exchanger systems have been
used since the late 1970s and have become the most
common system in residential geothermal heat pump
markets. These ground heat exchangers are commonly
installed in one of three con gurations: vertical closed-
loop ground heat exchangers (“vertical loops”), horizontal
closed-loop ground heat exchangers (“horizontal loops”)
and “pond or lake loop”. Each con guration uses the
moderate temperatures of the earth as a heat source and/
or heat sink (Fig 30, 31, 32). Piping con gurations are
typically reverse return header type.
Both horizontal and vertical designs are used
predominantly and the type installed depends on local
practices, site conditions and the geothermal heat
pump. The energy ef ciency of the system is dependent
upon suf cient ground loop to produce favorable water
temperatures for the geothermal heat pump. In addition
to adequate loop length, individual trenches or boreholes
also must be separated suf ciently to avoid thermal
interference. Vertical loops are generally more expensive
to install than horizontal loops, but require less piping and
less land area in most cases.
Fig. 30 Closed loop vertical design
Fig. 31 Closed loop horizontal design
Fig. 32 Closed loop pond or lake design