Viessmann Vitocal 222-G User Manual page 124

Vitocal 200-S/222-S/242-S
5.2 Vitocal 200-S, type AWB-AC, one heating circuit without mixer, with DHW heating and
active cooling via heating circuit A1
ID: 4605229_1304_08
Application range
Detached houses with uniform user patterns, underfloor heating and
cooling demand. Size the DHW cylinder in accordance with current
standards and requirements.
Main components
■ Vitocal 200-S, type AWB-AC, with Vitotronic 200 control unit, type
WO1C
■ One heating circuit without mixer
■ DHW cylinder
Requirements
The minimum flow rate of the heat pump must be safeguarded by sec-
ondary pump 6 and overflow valve oW. The heating line and overflow
valve must be matched up hydraulically.
Central heating by heat pump
Heat pump 1 starts if the actual temperature captured by the flow
temperature sensor in heat pump internal unit 1 is lower than the set
temperature selected at control unit 2. Heat pump 1/wO supplies
heating circuit oP with heat. Control unit 2 in heat pump internal unit
1 regulates the heating water flow temperature and thereby the heat-
ing circuit.
Secondary pump 6 in internal unit 1 delivers the heating water via
3-way diverter valve 5 either to DHW cylinder eP or to heating circuit
oP. Opening and closing the valves at the underfloor heating system
distributor regulates the flow rate within the heating circuit. Once the
actual flow temperature value at the flow temperature sensor inside
internal unit 1 exceeds the set temperature selected at the control
unit, heat pump 1/wO and secondary pump 6 are switched off.
Required parameter settings
ID: 4605229_1304_08
Parameter
7000
7100
7101
7103
7111
71FE
2003
System examples
(cont.)
Value Function
2 With heating circuit A1/HC1, DHW cylinder (delivered condition)
3 Active cooling
1 Cooling via heating circuit A1/HC1
180 Min. flow temperature, cooling
4 Cooling curve slope
1 Enable active cooling
1 Vitotrol 200A or 300B remote control activated for heating circuit A1/HC1
DHW heating
In the delivered condition, DHW heating by heat pump 1/wO is given
priority over the heating circuits and takes precedence at night. The
heat demand is issued via cylinder temperature sensor eQ and control
unit 2, which regulates secondary pump 6 and the internal 3-way
diverter valve. The control unit raises the flow temperature to the value
required for DHW heating.
Control unit 2 switches 3-way diverter valve 5 to the heating circuit
when the actual temperature at cylinder temperature sensor eQ
exceeds the set value selected at control unit 2. The DHW can be
reheated by a booster heater (e.g. an immersion heater in the DHW
cylinder) or with integral instantaneous heating water heater 4, to
raise the temperature to over 65 °C. Integral instantaneous heating
water heater 4 can also be used for covering peak loads (mono
energetic operating mode).
Active cooling function
The active cooling function is enabled by control unit 2 if the value
for the cooling limit temperature that can be adjusted at control unit
2 is exceeded at outside temperature sensor 3. Heat pump 1/
wO and secondary pump 6 start. Reversing the refrigerant circuit
cools the water that is transported into cooling circuit oP.
The set flow temperature is controlled via flow temperature sensor
iU and control unit 2. Contact humidistat iE (not required in con-
junction with internal units with a dehumidifying function) and frost stats
qI ensure that no condensation and therefore damage can occur due
to low temperatures.
Note
All lines where the cold water temperature can fall below the dew point
should be insulated so that they are vapour diffusion-proof.
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VIESMANN
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