Control Sequence - Viessmann Vitotronic 100 Installation And Service Instructions Manual

Function description
Cylinder temperature control
The set value range can be extended to 90 °C via cod-
ing address "56" in group 3 "DHW".
Auxiliary function for DHW heating
Select a second set DHW temperature in coding
address "58" in the "DHW" group. This function is ena-
bled by setting the fourth DHW time phase for DHW
heating.

Control sequence

Code "55:0", cylinder heating
The DHW cylinder goes cold (set value
ble at coding address "59"):
The set boiler water temperature is set 20 K higher
■
than the set DHW temperature (adjustable via coding
address "60").
Note
The value set in coding address "06" in group 2
"Boiler" for the maximum boiler water temperature
limit has no effect.
■ Pump on:
– Starts the circulation pump for cylinder heating
subject to the boiler water temperature (code
"61:0").
The circulation pump starts when the boiler water
temperature is 7 K higher than the DHW tempera-
ture.
– Immediate start of the circulation pump for cylinder
heating (code "61:1").
The DHW cylinder is hot (set value +2.5 K):
The set boiler water temperature is returned to the
■
selected set value.
Pump run-on:
■
The circulation pump runs on after cylinder heating
until one of the following criteria is met:
– The differential between the boiler water tempera-
ture and the DHW temperature is less than 7 K.
The set DHW temperature is exceeded by 5 K.
–
The set max. run-on time is reached (coding
–
address "62").
■ Without pump run-on (code "62:0").
64
(cont.)
System with solar control unit
A third set DHW temperature can be specified via cod-
ing address "67" in group 3 "DHW".
The DHW cylinder is only reheated by the boiler if the
temperature falls below this value.
Code "55:1", adaptive cylinder heating
2.5 K, adjusta- With adaptive cylinder heating, the speed of the tem-
-
perature rise during DHW heating is taken into
account.
The DHW cylinder goes cold (set value
able via coding address "59"):
■ The set boiler water temperature is set 20 K higher
than the set DHW temperature (adjustable via coding
address "60").
Note
The value set in coding address "06" in the "Boiler"
group for the maximum boiler water temperature limit
has no effect.
Pump on:
■
Starting the circulation pump for cylinder heating
–
subject to the boiler water temperature (code
"61:0"):
The circulation pump starts when the boiler water
temperature is 7 K higher than the DHW tempera-
ture.
Immediate start of the circulation pump for cylinder
–
heating (code "61:1").
The DHW cylinder is hot:
■ The control unit checks whether the boiler will be
required to supply heat after the cylinder has been
heated up or whether residual boiler heat should be
transferred to the DHW cylinder.
Accordingly, the control unit determines the burner
and circulation pump shutdown points to prevent the
set DHW temperature being substantially exceeded
after the cylinder has been heated up.
Operating instructions
2.5 K, adjust-
−