Viessmann Vitocal 222-G User Manual page 76

Vitocal 300-G/350-G
4.3 Vitocal 300-G/350-G with one heating circuit without mixer, one heating circuit with
mixer, DHW heating, heating water buffer cylinder and active cooling function via AC-Box
(2-pipe version), with fan convector
ID: 4605351_1304_03
Application range
Detached house with two heating circuits with different design layouts.
Size DHW cylinder wP in accordance with current standards and
requirements. Cooling via a separate cooling circuit e.g. in conjunction
with fan convectors rE.
Main components
■ Vitocal 300-G/350-G, type BW or BWC, up to 17 kW
■ Vitotronic 200, type WO1B
■ DHW cylinder
■ Heating water buffer cylinder
■ AC-Box
Heating water buffer cylinder
The minimum flow rate of heat pump 1 is safeguarded via heating
water buffer cylinder eP and secondary pump 6. It is possible to use
differential pressure-dependent heating circuit pumps tT and zE.
Central heating by heat pump
Heat pump 1, primary pump 5 and secondary pump 6 start when
the actual temperature captured by cylinder temperature sensor eQ of
heating water buffer cylinder eP falls below the set temperature selec-
ted at control unit 2.
Control unit 2 regulates the heating water flow temperature. Subject
to demand, secondary pump 6 delivers heating water via heating
water buffer cylinder eP to the heating circuit, or via circulation pump
for cylinder heating 7 to DHW cylinder wP.
Type BWC:
Subject to demand, integral secondary pump 6 or circulation pump
for cylinder heating 7 delivers heating water either to the heating cir-
cuits or DHW cylinder wP.
Required parameter settings
ID: 4605351_1304_03
Parameter
7000
7100
7101
7104
7111
System examples
(cont.)
Value Function
6 With heating circuit A1/HC1, M2/HC2, DHW cylinder
3 Active cooling
4 Cooling via separate cooling circuit
50 Influence room temperature hook-up cooling circuit
4 Cooling curve slope
Heating circuit pumps tT and zE deliver the required water volume to
the heating circuits. The flow rate in the heating circuit is regulated by
opening or closing the thermostatic radiator valves or the valves of the
underfloor heating distributor.
To balance the difference in energy between the primary and secon-
dary circuits, operate heating water buffer cylinder eP. Any heat not
absorbed by the heating circuits is stored in heating water buffer cyl-
inder eP. In addition, heat pump 1 achieves longer runtimes, and the
heating circuits are supplied with heat from heating water buffer cylin-
der eP during power-OFF periods.
DHW heating by heat pump
In the delivered condition, DHW heating by heat pump 1 is given
priority over the heating circuits and takes precedence at night.
The heat demand is issued via cylinder temperature sensor wQ and
control unit 2, which controls circulation pump for cylinder heating
7. The control unit raises the flow temperature to the value required
for DHW heating.
Type BWC:
The heat demand is issued via cylinder temperature sensor wQ and
control unit 2, which controls integral circulation pump for cylinder
heating 7.
The flow temperature can be raised above 60 °C with instantaneous
heating water heater 4.
Active cooling function via AC-Box
The building can be cooled with heat pump control unit 2 in conjunc-
tion with AC-Box qZ (accessories). The natural cooling function is
enabled by control unit 2 for the cooling circuit as soon as the thresh-
old temperature (cooling limit temperature) that can be selected at
control unit 2 is exceeded. The valves in the AC-Box are set to natural
cooling. Heat is extracted from the cooling circuit and transferred to
the ground. If the cooling capacity is insufficient, the internal valves in
the AC-Box are set to active cooling and heat pump 1 starts. This
causes heat to be extracted from cooling circuit rP, and transferred
via heat pump 1 to consumer groups wP, eP, tP and zP. If there is
no consumer demand, the heat is transferred to the ground via probe
qW.
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VIESMANN
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