Viessmann Vitotronic 11 CC1E, Installation And Service Instructions Manual

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102
Multi boiler systems with shunt pumps for every
boiler
■ Temperature sensors T1 and T2 capture the return
temperature at different test points.
■ The shunt pump is started via temperature sensor T2
if the factory-selected minimum return temperature
(specified by the coding card) is not being achieved.
■ If the minimum return temperature captured by tem-
perature sensor T1 is not achieved despite return
temperature raising, the flow rate will be reduced via
the butterfly valve. Where temperature sensor T1
cannot affect the butterfly valve, it must regulate the
downstream heating circuits instead.
Multi boiler systems with boiler circuit pump and
3-way mixing valve
■ Temperature sensor T1 captures the return tempera-
ture.
■ The flow rate is proportionally reduced via the 3-way
mixing valve on the boilers if the factory-selected set
temperature (specified by the coding card) is not
achieved.
■ If the set temperature is exceeded, the 3-way mixing
valve is opened. The flow rate is always increased to
100 %.
Multi boiler systems with boiler circuit pump, low
loss header and 3-way mixing valve
■ Temperature sensor T1 captures the return tempera-
ture.
■ The flow rate is proportionally reduced via the 3-way
mixing valve on the boilers if the factory-selected set
temperature (specified by the coding card) is not
achieved.
■ If the set temperature is exceeded, the 3-way mixing
valve is opened. The flow rate is always increased to
100 %.
■ Downstream heating circuits are hydraulically sepa-
rated.
■ The flow temperature is specified by the higher rank-
ing third party control unit.
Connection in heating systems without LON
Single boiler system
■ Plug
sÖ
A1 of the Vitotronic is used as a switching
contact.
■
Required parameter: "53:2" in the "General" group
20 A1
A
B
20
close close close
N L
K
1 2 n
Fig. 39
sÖ A1 Closing of mixers
A
Contactor relay, part no. 7814 681
B Downstream heating circuit controller, switching
contact closed:
Signal for mixer CLOSE
Multi boiler system
■ Plug sÖ A1 of the Vitotronic is used as a switching
contact.
■ Required parameter: "0D:1" in the "Boiler" group
and "53:2" in the "General" group
K3
K1 K2
L1
N
PE
1 2 ... n
A
A1
sÖ
A1
sÖ
K1
N L1
K2
N L1
A
C
B
D
A
Fig. 40
sÖ
A1 Closing of mixers
A
Contactor relay, part no. 7814 681
B
Downstream heating circuit controller, switching
contact closed:
Signal for mixer CLOSE
C
Power supply, 230 V/50 Hz
D
Junction box, on site
Function description
Boiler water temperature control
(cont.)
5863679
Functions