Viessmann VITOTRONIC 200 Installation And Service Instructions Manual page 59

Vitotronic 200, HO1B and 300-K, MW2C Installation/Service
Heating Circuit Control Unit of the Vitotronic 300-K
Function Description, Vitotronic 200/300-K
(continued)
Room temperature
In conjunction with a remote control and room
temperature hook-up (coding "b0" in the "Heating
circuit...") group:
Compared with the outdoor temperature, the room
temperature has a greater influence on the set supply
temperature (changed at coding "b2" in the "Heating
circuit..." group).
In conjunction with heating circuits with mixing valve:
For control differentials (actual value deviation) above
4°F (2 K) room temperature, the influence can be
increased further (coding "b6" in the "Heating circuit..."
group):
H Quick heat-up
The set room temperature must be raised by at least
4°F (2 K) by the following measures:
– Enabling comfort mode
– Changing from central heating with reduced
temperature to central heating with standard
temperature
– Start optimization (coding "b7" in the "Heating
circuit..." group)
Quick heat-up will stop when the set room
temperature has been reached.
H Quick setback
The set room temperature must be reduced by at least
4°F (2 K) by the following measures:
– Activating economy mode
– Changing from central heating with standard
temperature to central heating with reduced
temperature
– Shutdown time optimization (coding "c1" in
the "Heating circuit..." group).
Quick setback ends when the set room temperature
has been reached.
DHW temperature
Priority control
H With priority control: (coding "a2:2" in the "Heating
circuit..." group):
During tank heating, the set supply temperature is
set to 32°F (0°C).
The mixing valve closes and the heating circuit pump is
switched off.
H Without priority control:
The heating circuit control unit continues to operate
with the same set value.
Heating circuit pump logic (economy mode)
The heating circuit pump is switched off (set supply
temperature set to 32°F (0°C) if the outdoor temperature
exceeds the value selected at coding "a5" in the "Heating
circuit..." group.
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