Viessmann Vitotronic 11 CC1E, Installation And Service Instructions Manual

Page: 104 / 120

104
Brief description
■ The set boiler water temperature for DHW heating is
regulated to a constant value (cylinder temperature
control). It operates by starting and stopping the cir-
culation pump for cylinder heating.
The switching differential is
±
2.5 K.
■ When the DHW cylinder is heated, a set boiler water
temperature is specified that is 20 K higher than the
set DHW temperature (adjustable at parameter "06"
in the
"DHW" group).
Functions
Frost protection
The DHW cylinder will be heated to 20 °C if the DHW
temperature falls below 5 °C.
Additional function for increased DHW heating
This function is activated by specifying a 2nd set cylin-
der temperature via parameter "03" in the
"DHW"
group. The frequency of the additional function for
increased DHW heating is set via parameter "09".
Set DHW temperature
The set DHW temperature can be adjusted between
10 and 60 °C.
Parameter "01" in the
"DHW" group enables the set
range to be extended to 95 °C.
System with cylinder loading system
The above functions also apply in conjunction with cyl-
inder loading systems.
Set the following parameters:
"00:3" in the
"DHW" group; "53:1", "55:2" in the "Gen-
eral" group.
The DHW cylinder is only reheated by the boiler if the
temperature falls below this value.
System with solar control unit
A 3rd set DHW temperature can be assigned at
parameter "0C" in the
"DHW" group.
The DHW cylinder is only reheated by the boiler if the
temperature falls below this value.
Control sequence
The following parameters in the "DHW" group influ-
ence the controlled sequence.
Tank heating (parameter "00:0")
The DHW cylinder goes cold (set value
–
2.5 K, adjust-
able via parameter "04"):
■ The set boiler water temperature is set 20 K higher
than the set DHW temperature (adjustable via
parameter "06").
■ Pump on:
– Starting the circulation pump for cylinder heating
subject to boiler water temperature (parameter
"07:0").
The circulation pump starts when the boiler water
temperature is 7 K higher than the DHW tempera-
ture.
– The circulation pump for cylinder heating is started
immediately (parameter "07:1")
The DHW cylinder is hot (set value +2.5 K):
■ The set boiler water temperature is returned to the
selected set value.
■ With pump run-on:
The circulation pump runs on after cylinder heating
until one of the following criteria is met:
– The set DHW temperature is exceeded by 5 K.
– The set max. run-on time is reached (parameter
"08").
■ Without pump run-on (parameter "08:0")
Adaptive cylinder heating enabled (parameter
"00:1")
With adaptive cylinder heating, the speed of the tem-
perature rise during DHW heating is taken into
account.
Function description
DHW heating control (cylinder temperature control)
5863679
Functions