Operating instructions

100
Brief description
■ The boiler water temperature is regu-
lated by modulating the burner.
■ The set boiler water temperature is
determined from the following param-
eters:
– Set flow temperature of heating cir-
cuit A1 (system circuit) or the heat-
ing circuits connected via LON
– External demand
Cascade control of the Vitotronic 300-K
Brief description
The flow temperature is regulated by
starting or stopping the burners or by
starting/stopping individual burner
stages.
■ Standalone control (see page 101)
■ Sequential control (see page 101)
■ Subject to system version, we differ-
entiate between condensing strategy
(see page 102) and two conventional
boiler strategies (see page 104).
Set flow temperature
The set flow temperature is determined
from the following parameters:
■ Set flow temperature of heating circuit
without mixer A1 (heating circuit 1) and
heating circuits with mixer M2 (heating
circuit 2) and M3 (heating circuit 3).
■ Set flow temperature of additional con-
sumers.
■ Set DHW temperature.
■ External demands.
Upper control range limits:
Maximum limit of the system flow tem-
perature (coding address "37" in the
"Cascade" group).
Lower control range limits:
Minimum limit of the system flow tem-
perature (coding address "36" in the
"Cascade" group).
Function description, Vitotronic 100 and Vitotronic 300-K
Boiler control unit Vitotronic 100, type GC4B
5815 091 GB