Viessmann Vitoligno 300-P Service Instructions For Contractors page 108

Function description
Control functions
Cylinder temperature control
Brief description
■ The cylinder temperature control is a
constant temperature control. This is
the result of starting and stopping the
circulation pump for cylinder heating.
The switching differential is ±2.5 K.
■ When the DHW cylinder is heated up,
a set boiler water temperature is
defaulted that lies 15 K above the set
DHW temperature (adjustable via cod-
ing address "60").
■ During cylinder heating, central heat-
ing is switched OFF (optional cylinder
priority).
■ Coding addresses that influence the
cylinder temperature control:
54, 55, 56, 58, 59, 60 to 62, 64, 67, 70
to 75, 7F, 84, 85, A2.
For a description, see codes overview.
Functions
Time program
An automatic program or an individual
time program may be selected for DHW
heating and the control of the DHW cir-
culation pump.
Compared with the heating circuit heat-
up phase, DHW heating starts 30 min
earlier in automatic mode.
The individual time program enables up
to four periods per day to be set via the
time switch to control DHW heating and
four periods for the DHW circulation
pump.
All cylinder heating sequences will be
completed independent of the time pro-
gram.
108
(cont.)
In conjunction with coding address
"7F"
■ Detached house
Code "7F:1":
– Automatic operation
For systems with two heating cir-
cuits, the heating times for heating
circuit 1 are applied.
– Individual time program
The switching times for DHW heat-
ing and the DHW circulation pump
have the same effect on all heating
circuits.
■ Apartment block
Code "7F:0":
– Automatic mode
For systems with two heating cir-
cuits, the heating times for the indi-
vidual heating circuit are applied.
– Individual time program
The switching times for DHW heat-
ing and the DHW circulation pump
can be adjusted individually for each
heating circuit.