Function Description - Vitotronic 100 Boiler Temperature Control - Viessmann Vitotronic 100 GC1 Installation And Service Instructions Manual

Function description – Vitotronic 100
Boiler temperature control
Brief description
The boiler water temperature is
regulated by controlling a two stage
or modulating burner.
The set boiler water temperature
set-point is controlled by Vitotronic
300-K, MW1S.
Functions
The boiler water temperature is
monitored by three sensors separately,
which are inserted into a multiple
sensor well:
Fixed high limit (STB)
(liquid expansion)
Adjustable high limit TR
(liquid expansion)
Boiler temperature sensor KTS
(changes in resistance PT500)
Control range limits top
Fixed high limit STB 120 ˚C /
248 ˚F, adjustable to 110 or
100 ˚C/ 230 or 212 ˚F
Thermostat TR 95 ˚C / 203 ˚F,
adjustable to 87, 100 or 110 ˚C /
187, 212 or 230 ˚F.
Electronic maximum limiter
Setting range: 20 to 127 ˚C /
68 to 261 ˚F
The maximum boiler water
temperature limit can be adjusted
via coding address 06.
Control sequence
Boiler goes cold
(set value –2 K)
The burner is activated if the oiler
termperature is 2 ˚C / 3.6 ˚F below
the calculated set point temperature.
The burner may be delayed a few
minutes depending on the connected
auxilliary equipment and the fuel type.
106
Coding addresses which influence
the boiler temperature control
02 to 06, 08 to 0b, 13 to 1C
For a description, see the coding
overview.
Lower control range limits
In standard mode and when frost
protection is active, the control unit
regulates the boiler water temperature
in accordance with the respective
boiler.
Boiler heats up
The burner shutdown point is
determined by the switch-off
differential (coding address 13).