Viessmann Vitolig
200 Technical Manual page 60

5.6 Application examples
Application example 1
one or two heating circuits with mixer
Notes
The temperatures stated in the
application example are standard values;
set alternative values according to the
relevant requirements.
The heating circuits and one DHW
cylinder are heated by Vitolig and one
heating water buffer storage unit.
Combustion controller and control of the
Vitolig circulation pump
After Vitolig has been heated up, it is
operated at full load. The boiler circuit
pump 3 is switched on, when Vitolig
reaches a boiler water temperature of
60 ºC.
Either the heating circuit or the DHW
cylinder are heated up. The heat not
drawn off by consumers is transferred to
the heating water buffer storage unit.
The boiler circuit pump 3 is switched
off, when the boiler water temperature
falls below 50 ºC, if the fuel has been
consumed and the flue gas temperature
has fallen.
Return temperature raising facility
Vitolig requires a minimum return
temperature of 45 ºC. When the boiler
circuit pump 3 is switched on, the
mixing valve 4 opens the path from the
heating return to Vitolig in line with the
rising return temperature and
simultaneously closes the path from the
flow to the return (bypass).
Vitolig 100 incl. DHW cylinder, heating water buffer storage unit and
DHW heating with priority control
After Vitolig is started, initially the DHW is
heated up; space heating is only provided
afterwards.
The Vitolig boiler water temperature is at
least 60 ºC; the boiler circuit pump 3
runs to raise the return temperature. The
DHW circulation pump 5 operates, if the
temperature inside the DHW cylinder falls
below the value set at the Vitotronic 050,
providing the value set at the heating
water buffer storage unit thermostat qP is
exceeded. If the flow rate of the boiler
circuit pump 3 is higher than that of
circulation pump 5, any surplus heat
will be transferred to the heating water
buffer storage unit. The three−way mixer
8 of the heating circuit is closed when
DHW is heated. The circulation pump 5
is switched off, when the set temperature
has been reached, and the three−way
mixer 8 opens, transferring heat into the
heating circuit.
DHW heating without priority control
To change to "without priority" change
coding "A2" from "A2:2" to "A2:0" at the
Vitotronic 050. Depending on the
prevailing demand, either DHW and/or
space heating is provided, when Vitolig
starts up.
In that case both circulation pumps 5
and 7 transfer heat from Vitolig and
from the heating water buffer storage unit
to the relevant consumer.
DHW heating through the heating water
buffer storage unit
The Vitolig boiler water temperature lies
below 55 ºC; the temperature of the
heating water buffer storage unit at
thermostat qP lies above 65 ºC or at least
10 K higher than the DHW temperature
set at Vitotronic 050. When DHW heating
is requested, the DHW circulation pump
5 activates, and the DHW cylinder is
heated by the heating water buffer
storage unit.
5 Vitolig 100
Heating mode
The heat created by Vitolig is transferred
via boiler circuit pump 3 to the heating
circuit and to the heating water buffer
storage unit. The heat, which is not
required by the heating circuit, is
transferred to the heating water buffer
storage unit.
If the Vitolig boiler water temperature
falls, a greater amount of heat is drawn
from the heating water buffer storage
unit, the more the mixing valve 4 of the
return temperature raising facility opens
the path from the boiler flow (bypass).
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