D Enable 3-Way Diverter Valve Heating/Dhw - Viessmann VITOTRONIC 200 Service Instructions Manual

730D Enable 3-way diverter valve heating/DHW

If a pump and a 3-way diverter valve are used in the
secondary circuit to switch between DHW heating and
central heating, set parameter "Enable 3-way diverter
valve heating/DHW 730D" to "1".
When using 2 pumps (secondary pump and circulation
pump for cylinder heating), set this parameter to "0".
730E Start threshold
Start threshold for instantaneous heating water
heater and lag heat pump
To prevent the additional heat source starting immedi-
ately if the set temperature is not reached for a short
time, the heat pump control unit uses the output inte-
gral as start criterion. This integral is formed from the
duration and extent of the deviation of the actual flow
temperature from the set flow temperature. The output
integral is the grey area between the actual flow tem-
perature curve and the set temperature line. Therefore
the unit of the output integral is K
C
Fig. 57
Set flow temperature
A
Actual flow temperature
B
Output integral
C
Note
Subject to economic and ecological factors, the load
manager inside the control unit decides whether to
start the instantaneous heating water heater or a lag
heat pump.
730F Compressor performance at min. outside temperature
On heat pumps using compressors with output-
dependent control: Default compressor output.
In the starting phase, the compressor is regulated to a
constant output, in order to improve the control charac-
teristics of the output controller.
!
min.
·
A
B
t
Parameter group Internal hydraulics
!
Value Meaning
"0" No 3-way diverter valve installed.
■
DHW heating is provided via different hy-
■
draulic circuits from central heating using a
circulation pump for cylinder heating (on the
heating water side).
Secondary pump switched off for DHW
■
heating.
"1" 3-way diverter valve installed.
■
Secondary pump runs for DHW heating.
■
Level or output matching, modulating heat pumps
In modulating heat pumps (e.g. Vitocal 300-A), when a
large difference arises between the actual and set flow
temperature in the secondary circuit, the compressor
will be regulated to an output of 100 %. The compres-
sor output will not be reduced until this difference
decreases.
The set value indicates the degree of reduction. A
higher value results in a more pronounced reduction.
Start threshold for active cooling in weather-com-
pensated cooling mode
For active cooling, the set flow temperature must be
exceeded in weather-compensated cooling mode. At
the same time the integral from actual flow tempera-
ture to set flow temperature must exceed the set value.
The compressor output required for this is also calcula-
ted from this integral.
Setting in K min
·
!
This output can be specified separately for minimum
and maximum outside temperature. Output values for
temperatures between these are calculated using lin-
ear interpolation.
229