Viessmann Vitosol
100 Technical Manual page 83

Additional function for DHW heating
Possible only in conjunction with Vitotronic control units with KM BUS and connection extension.
In systems with a cylinder capacity above
400 litres, the entire water contents must
be heated to 60 ºC once every day. For
this, an additional circulation pump D
can be started (for connection to
connecting extension, see page 82).
Thermostat function
You can use the thermostat function
independent of the solar operation,
e.g. for utilising excess heat.
Thermostat start−up temperature TO and
thermostat shutdown temperature TF are
adjustable.
Maximum cylinder temperature control
The solar circuit pump is switched OFF , if
the set maximum cylinder temperature
has been exceeded, to prevent
overheating the DHW cylinder.
Collector cooling function
The solar circuit pump is switched OFF
when the set maximum cylinder
temperature is reached.
Reverse cooling function
When the collector cooling function has
been activated, the cylinder temperature
may continue to rise, but no higher than
90 ºC (cylinder safety shutdown).
Heat statement
The heat value is calculated using the
differential between the collector and
cylinder temperature, the selected
Minimum temperature/frost protection
You can select a minimum start−up
temperature for the solar circuit pump.
This prevents the pump being started too
frequently.
VITOSOL
At the boiler control unit,
H a second set DHW cylinder temperature
must be encoded
H the fourth DHW phase for DHW loading
must be activated.
As delivered condition
TO = 40 ºC,
TF = 45 ºC
Setting range:
0 to 90 ºC
If the collector temperature rises to the
set maximum collector temperature, the
pump is switched ON until the actual
temperature falls 5 K below that value
again. In this case, the cylinder
temperature may continue to rise, but no
higher than 90 ºC (safety shutdown).
In the evening, the pump continues to run
until the DHW cylinder has cooled down
to the maximum cylinder temperature via
the collector and interconnecting
pipework.
volume flow, the type of process medium
and the hours run by the solar circuit
pump.
4.7 Additional Vitosolic 100 functions
This signal is transferred via the KM BUS
to Vitosolic 100, and the circulation pump
will be started.
TO = TF: Thermostat function inactive;
relay 2 starts, when the
maximum cylinder temperature
is exceeded
TO > TF: Thermostat function for
utilising excess heat
TO < TF: Thermostat function for
reheating
83