4.8 Vitocal 300-G/350-G, two-stage, 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 cooling convector
Note
For two heat pumps with a total output (stage 1 + stage 2) of max. 34 kW. Stage 1 may have a max. output of 17 kW and active cooling only
takes place via stage 1.
ID: 4605356_1304_03
Application range
Large luxurious detached houses, apartment buildings and buildings
for commercial use with two heating circuits with different design lay-
outs. Size DHW cylinder
eP
in accordance with current standards and
requirements. Cooling via a separate cooling circuit e.g. in conjunction
with cooling convectors
iW
.
Main components
■ Vitocal 300-G/350-G, type BW
■ Vitocal 300-G/350-G, type BWS
■ Vitotronic 200, type WO1B
■ Heating circuit distributor with one heating circuit without mixer and
one heating circuit with mixer
■ DHW cylinder
■ Heating water buffer cylinder
■ AC-Box (active cooling)
■ Separate cooling circuit
Heating water buffer cylinder
The minimum flow rate of heat pump stages
1
/
9
is safeguarded via
heating water buffer cylinder
zP
and secondary pumps
6
/
qP
. It is
possible to use differential pressure-dependent heating circuit pumps
uZ
and
oZ
.
Central heating by heat pump
Stage 1
1
, primary pump
5
and secondary pump
6
start when the
actual temperature captured by cylinder temperature sensor
zQ
of
heating water buffer cylinder
zP
falls below the set temperature selec-
ted at control unit
2
.
If the output of stage 1 is insufficient, i.e. the integral derived from the
duration and amount of the deviation between the set and actual val-
ues of the flow temperature exceeds the value specified at control unit
2
, then stage 2
9
plus primary pump
wT
and secondary pump
qP
are also started to raise the heating output.
Control unit 2 regulates the heating water flow temperature. Subject
to demand, secondary pumps
6
/
qP
deliver heating water to the heat-
ing water buffer cylinder, or via circulation pump for cylinder heating
7
to DHW cylinder
eP
.
Heating circuit pumps
uZ
and
oZ
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 water volume between the primary and
secondary circuits, operate heating water buffer cylinder
zP
in parallel
to the heating circuits. Any heat not absorbed by the heating circuits
is stored in heating water buffer cylinder
zP
. In addition, heat pump
1
achieves longer runtimes, and the heating circuits are supplied with
heat from heating water buffer cylinder
zP
during power-OFF peri-
ods.
Both stages
1
/
9
of the heat pump will restart when the temperature
at temperature sensor
zQ
in heating water buffer cylinder
zP
falls
below the set value.
DHW heating by heat pump
In the delivered condition, DHW heating through stage 1
1
takes pri-
ority over the heating circuits.
The heat demand is issued via cylinder temperature sensor
eW
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.
The flow temperature can be raised above 65 °C with instantaneous
heating water heater
4
.
Active cooling function via AC-Box
The building can be cooled with heat pump stage 1
1
in conjunction
with AC-Box
iP
(accessories). The natural cooling function is enabled
by control unit
2
for the cooling circuit as soon as the threshold tem-
perature (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 stage 1
1
starts. This causes
heat to be extracted from cooling circuit
iQ
, and transferred via heat
pump stage
1
to consumer groups
eP
,
zP
,
uP
and
oP
. If there is no
consumer demand, the heat is transferred to the ground via probe
wU
.
Required parameter settings
ID: 4605356_1304_03
Parameter Value Function
7000 6 With heating circuit A1/HC1, M2/HC2, DHW cylinder
71FE 1 Enable active cooling
7100 3 Active cooling
7101 4 Cooling via separate cooling circuit
7103 100 Min. flow temperature cooling (delivered condition)
5030 according to type plate Rated heating output, heat pump stage 1
5130 according to type plate Rated heating output, heat pump stage 2
Vitocal 300-G/350-G
(cont.)
110
VIESMANN
System examples
4
5822 472 GB
To Next Page
Loading...
