Viessmann VITOLIGNO 300-P Service Instructions Manual page 115

Control functions
Functions
The flow temperature of heating circuits
1 and 2 is captured by the flow temper-
ature sensor.
Time program
In accordance with the times program-
med in the "Heating and DHW" program,
the control unit time switch regulates
between central heating with standard
room temperature and central heating
with reduced room temperature.
Every operating mode has its own set
level.
Outside temperature
A heating curve must be set up for
matching the control unit to the building
and the heating system (see page 41).
The heating curve characteristics deter-
mine the set boiler water temperature
subject to outside temperature. The con-
trol unit uses an average outside tem-
perature. This comprises the actual and
the adjusted outside temperature.
Room temperature
In conjunction with the remote control
and room temperature hook-up (coding
address "B0"):
Compared to the outside temperature,
the room temperature has a greater influ-
ence on the set boiler water temperature
(change via coding address "B2").
(cont.)
DHW temperature
■ With priority control:
■ Without priority control:
■ With modulating priority control in con-
Heating circuit pump logic (economy
mode)
The heating circuit pump is switched off
(set flow temperature set to 0 °C) when
the outside temperature exceeds the
value selected via coding address "A5".
Extended economy mode
The heating circuit pump is switched off
and the set flow temperature is set to
0 °C if one of the following criteria is
met:
■ The outside temperature exceeds the
■ The set room temperature is reduced
Function description
The set flow temperature will be adjus-
ted to 0 °C during cylinder heating.
The mixer closes and the heating cir-
cuit pump is switched off.
The heating circuit pump continues to
operate with the same set value.
junction with heating circuits 1 and 2:
The heating circuit pump remains
switched on. The set flow temperature
of the heating circuit will be reduced
until the set boiler water temperature
has been reached during cylinder
heating. This is subject to the differen-
tial between the set and the actual
boiler water temperatures, the outside
temperature, the heating curve slope
and the setting of coding address
"A2".
value selected via coding address
"A6".
via coding address "A9".
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