Bin the case of control with buffer or combi storage tank, the upper buffer storage tank
sensor (B4), the lower buffer storage tank sensor (B41) and the relevant source sensor
must be installed.
If the lower buffer storage tank sensor (B41) is missing, the controller uses the return
temperature sensor (B71) for switching the heat pump off.
B41 is not considered for the buffer full charge if a solar application is configured. It is
always switched off with B71. B41 is reserved for the solar function.
Both stages for a 2-stage heat pump remain in operation until the buffer is fully
charged.
Compressor settings
The settings apply to compressor 1 and – if present – to compressor 2.
Line no.
Operating line
2841
Keep compr run time min
2842
Compressor run time min
2843
Compressor off time min
2844
Switch-off temp max
2845
Red switch-off temp max
2852
LP delay on startup
This determines if the minimum compressor running time set on operating line 2842
shall be observed if the heat request is stopped prematurely:
Keep compr run time
min
No
No consideration is given to the minimum compressor running time. When there is no
more heat request, the compressor is switched off.
Yes
The minimum compressor running time is also observed when there is no more heat
request.
To prevent damage to the compressor due to too frequent switching cycles, the
compressor always operates for at least the period of time set here, each time it is
switched on. During storage tank charging and in the case of active limitations, the
minimum compressor running time is inactive.
Compressor run time
min
For the same reason, the compressor remains switched off for the minimum period of
time set here.
Compressor off time min
If the flow or the return temperature exceeds the
maximum switch-off temperature, the compressor will be switched off.
Switch-off temperature maximum
The heat pump is switched on again when the temperature at both sensors has
dropped by the "Switching diff return temp" (2840) below the maximum switch-off
temperature and the minimum off time has elapsed.
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Siemens Switzerland Ltd
User manual RVS61.843, RVS41.813
CE1U2355en_02
HVAC Products
6 The settings in detail
28. September 2009