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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the heating engineer settings
18.10.2002
4.88 Heat exchanger pump operation for partial
diagram Sol 5
•
Heat exchanger pump operation alternative / parallel can be selected
In addition to alternative charging of the buffer and d.h.w. storage tank, solar collector
partial diagram Sol 5 (2 storage tank charging pumps) allows parallel charging.
Setting range
Unit
Factory setting
1...2 –
2
Storage tank charging starts as soon as the required switching differential (temperature
differential ON, operating line 329 or 331) between the collector sensor and the rele-
vant storage tank sensor is reached:
1
Alternative operation
The 2 storage tanks are charged
alternately
depending on the selection
made on operating line 333 (priority with 2 storage tanks).
2
Parallel operation
As soon as the required collector flow temperature is reached, charging of
the storage tank selected on operating line 333 is started (priority with 2 stor-
age tanks). When the priority pump runs and the amount of heat delivered by
the collector is sufficient (during the “Maximum waiting time”, the collector
temperature does not drop below the “Temperature differential ON” by more
than half the switching differential), the second charging pump can
also
be
activated after the “Maximum waiting time” has elapsed (operating line
305
EXP
).
The second pump will be deactivated when the collector temperature drops
below the “Temperature differential ON” of the first pump by more than half
the switching differential, or when its own “Temperature differential ON” is not
reached, or when the respective storage tank is charged.
The following graph shows a possible process of parallel operation with selected rela-
tive priority for the d.h.w. storage tank:
2392Z46
TSx
K8
K12
ON
OFF
ON
OFF
=
=
=
=
TSx
Actual value of the solar collector temperature
when the storage tank temperature is constant
305
EXP
maximum waiting time
K12
Pump of heat exchanger 1
K8
Pump of heat exchanger 2
Benefit
Description
Setting
Effect
Parallel operation