Pump Or/And 3-Way Mixing Valve - Viessmann Vitotronic 11 CC1E Installation And Service Instructions Manual

Boiler water temperature control
20 A1
20
N L
A
K
close close close
1 2 n
B
Fig. 37
A1 Closing of mixers
sÖ
Contactor relay, part no. 7814 681
A
Downstream heating circuit controller, switching
B
contact closed:
Signal for mixer CLOSE
Multi boiler system
■ Plug sÖ A1 of the Vitotronic is used as a switching
contact for the Therm-Control.
■ Required parameter: "0D:1" in the "Boiler" group
and "53:2" in the "General" group
Boiler protection function: Raising the return temperature via shunt pump or/and 3-way mixing
valve
■ With shunt pump
For heating systems with distributor installed close to
the boiler
■ With 3-way mixing valve:
For heating systems where downstream heating cir-
cuits cannot be controlled, e.g. older systems or
commercial nurseries.
■ Conditions:
The boiler water flow rate must be able to be
–
reduced by at least 50 %.
– With shunt pump:
Size the shunt pump to approx. 30 % of the total
throughput.
– With 3-way mixing valve:
Size the boiler circuit pump at each boiler to
approx. 110 % of the total throughput.
Also affects the heating circuits.
■
(cont.)
L1
C
N
PE
A1
sÖ
N L1
K1
A
Fig. 38
A1 Closing of mixers
sÖ
Contactor relay, part no. 7814 681
A
Downstream heating circuit controller, switching
B
contact closed:
Signal for mixer CLOSE
Power supply, 230 V/50 Hz
C
Junction box, on site
D
Function
Single boiler systems and multi boiler systems
with shunt pump
■ 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.
The flow rate will be reduced via the mixers if the
■
minimum return temperature captured by tempera-
ture sensor T1 is not achieved despite return temper-
ature raising.
Single boiler systems with shunt pump and 3-way
mixing valve
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.
The flow rate will be reduced via the 3-way mixing
■
valve if the minimum return temperature captured by
temperature sensor T1 is not achieved despite return
temperature raising.
Function description
K1 K2
A1
sÖ
N L1
K3
K2
A
A
B
1
D
2 ... n
101