Siemens AVS75.390 - Remote Control; Frost Protection for the Heating Circuit; Cooling Circuit 1

87/221
Siemens Switzerland Ltd User manual RVS61.843 CE1U2355en_02
HVAC Products 6 The settings in detail 23. November 2007
Remote control
Line no. Operating line
HC1 HC2 HCP
900 1200 1500 Optg mode changeover
None ¦ Protection ¦ Reduced ¦ Comfort ¦ Automatic
In the case of external changeover via the Hx inputs, the operating mode to be used
can be selected.
Frost protection for the heating circuit
Frost protection for the heating circuit is always active and cannot be deactivated.
If the flow temperature falls below 5 °C, the controller switches on the heat source and
activates the heating circuit pumps – independent of the heating system’s current
operating mode.
When the flow temperature returns to a level above 7 °C, the controller switches off the
heat source and deactivates the heating circuit pumps after a waiting time of 5 minutes.
For a more detailed description, refer to page 95.
6.7 Cooling circuit 1
RG1
B9
Y23/Y24
B16
Q24
C
To be able to operate the cooling circuit, an appropriate partial
diagram “Heating / cooling“ must be used.
The system starts to operate in cooling mode when the room
temperature rises above the Comfort cooling setpoint (902).
The cooling function must be activated (901 = Auto) and
enabled in accordance with the time program (907).
Cooling mode is aborted when heating circuit 1 calls for heat,
or when there is a heat request from DHW or some other
heating circuit (only with active cooling).
In the case of passive cooling, DHW charging and heating
with some other heating circuit during cooling mode are
possible.
When using a 2- or 4-pipe system with heat pump and process reversing valve, the
controller acquires the current room temperature and compares it with the room
temperature setpoint in order to calculate the required flow temperature setpoint. If the
buffer storage tank temperature is sufficiently low, the cooling circuit draws the required
cooling energy from that buffer. If the temperature is not low enough, or if there is no
buffer storage tank, the heat pump is put into operation to be used as a refrigeration
machine (process reversal Y22).
2-pipe system
Q2
HK
T
Y1/Y2
B1
Q24
KK
T
Y23/Y24
B16
The cooling and heating circuits draw their
cooling / heating energy from the same
common flow.
When using a 4-pipe system, the controller acquires the current room temperature,
compares it with the room temperature setpoint and then calculates the required flow
Frost protection for the
heating circuit in
heating mode
Frost protection for the
heating circuit in cooling
mode
Cooling via common
heating / cooling pipe
Cooling via separate
cooling pipe