Siemens RVS41.813 User Manual page 135

Active and passive
cooling
Parameter setting
examples with active
and passive cooling
Siemens Switzerland Ltd
HVAC Products
Application example:
Q3
B21
B91
E15
P
E9 B81 E10
P P
K1/E11
B83
B92
B71
Y21
Q8/E14
In the case of plants that support both passive and active cooling, the controller
switches automatically from passive to active cooling, and vice versa. Simultaneous
active and passive cooling is not possible.
As long as the temperature acquired by the source inlet sensor (B91) lies below the
cooling request, cooling is passive.
If the source temperature exceeds the cooling request, the controller switches to active
cooling.
The HP partial diagram used must support this function (HP 22, 23, 42, 43).
If a source inlet sensor (B91) is used, the temperature acquired by the source outlet
sensor (B92) is used as the changeover criterion.
The 3 following parameter setting examples show heat pump plant diagrams that make
possible automatic changeover between active and passive cooling mode.
The actively produced cooling energy is delivered to the consumers via the heating /
cooling pipes.
For the passively produced cooling energy, parameter "During compressor operation"
can be used to select indirectly the pipes via which cooling energy shall be delivered to
the consumers:
Passive cooling while the compressor is off
The passive cooling enery is diverted to the heating / cooling pipe.
If there is a DHW request, it is satisfied by the heat pump via the common heating /
cooling pipe. If there is a cooling request at the same time, it cannot be satisfied.
Passive cooling while the compressor is on
Passive cooling is effected via the cooling pipe. If there is a DHW request, it is satisfied
by the heat pump via the heating / cooling pipe. If there is a cooling request at the same
time, it can simultaneously be satisfied via the cooling pipe.
If passive cooling is effected via the heating / cooling pipe, parameter "In passive
cooling mode" (3007) can be used to define whether the condenser pump shall be
switched on or off.
User manual RVS61.843, RVS41.813
6 The settings in detail
Y21 Y1/Y2
TWW
B4
B3
B41
KW
B9
Q2
B1
RG1
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