Operating instructions
32
Heating system designs
System version 9 (cont.)
Codes must be set on every Vitotronic 100.
Required coding
01 : 2 Multi−boiler system with cascade control via LON BUS
01 : 3 Multi−boiler system with external cascade control via switching
contacts
02 : 2 Modulating burner operation
*1
03 : 1 Oil fired operation (irreversible)
*1
0C : 1 Constant return temperature control
4d : 2 Boiler circuit pump on plug sL
Automatic changeover
4A: 1 Connecting temperature sensor T1 to plugaJA
Possible applications
e.g. older heating systems and/or
systems in nurseries where
downstream heating circuits cannot
be controlled.
The cascade and cylinder control
must be provided by a higher control
unit.
Temperature sensor T1 closes the
three−way mixing valve in proportion
and therefore ensures boiler
protection if the required minimum
return temperature is not achieved.
Note
Size the boiler circuit pumps for each
boiler so that their volume flow is at
least as large as the max. total
heating circuit volume flow.
Recommendation: 110 %
*1
If required.
5862730GB