Viessmann Vitocal 222-G User Manual page 62

Vitocal 200-G
(cont.)
3.5 Vitocal 200-G with one heating circuit without mixer, one heating circuit with mixer
with DHW heating (optional solar DHW heating), heating water buffer cylinder and natural
cooling function with NC-Box with mixer
ID: 4605364_1304_03
Application range
Detached house and apartment building with two different heating cir-
cuits and cooling demand. Size the DHW cylinder in accordance with
current standards and requirements.
Main components
■ Vitocal 200-G with Vitotronic 200, type WO1B
■ Heating circuit distributor with one heating circuit without mixer and
one heating circuit with mixer
■ DHW cylinder
■ Solar thermal system
■ Solar heat exchanger set
■ Heating water buffer cylinder
■ NC-Box with mixer
Heating water buffer cylinder
The minimum flow rate of the heat pump is safeguarded via heating
water buffer cylinder zP and secondary pump 6.
Central heating by heat pump
Heat pump 1, primary pump qT and secondary pump 6 start if the
actual return temperature is lower than the set temperature selected
at control unit 2.
Heat pump 1 supplies heating circuits uP/oP with heat. Control unit
2 regulates the flow temperature of heating circuits uP/oP. Subject
to demand, secondary pump 6 delivers heating water to heating cir-
cuits uP/oP, or via circulation pump for cylinder heating 7 to DHW
cylinder eP.
Once the actual return temperature value at the return temperature
sensor exceeds the set temperature selected at control unit 2, heat
pump 1 and primary pump qT are switched off.
System examples
DHW heating by heat pump
In the delivered condition, DHW heating by heat pump 1 is given
priority over heating circuits uP/oP and takes precedence at night.
The heat demand is issued via cylinder temperature sensor eW and
control unit 2, which controls circulation pump for cylinder heating
7. Heat pump 1 raises the flow temperature to the value required
for DHW heating.
DHW reheating can be provided by an electric booster heater (e.g.
immersion heater inside the DHW cylinder).
If the set cylinder temperature selected at control unit 2 is exceeded,
the control unit switches circulation pump for cylinder heating 7 off
and starts secondary pump 6 in the case of heat demand from heat-
ing circuits uP/oP. Heating circuits uP/oP are supplied with heat.
The flow temperature can be raised above 65 °C with instantaneous
heating water heater 4.
Solar DHW heating (option)
Heat pump control unit 2 in Vitocal 200-G can be connected via KM
BUS distributor 8 to a Vitosolic 100 (type SD1) rU to achieve solar
DHW heating.
Circulation pump rE in Solar-Divicon rW starts and DHW cylinder
eP is heated up when the temperature differential between collector
temperature sensor rR and cylinder temperature sensor eQ exceeds
the set value.
The heat pump will be locked out against cylinder heating when the
temperature at cylinder temperature sensor eW in the DHW cylinder
exceeds the set value selected at the control unit.
The solar thermal system heats the cylinder to the set value selected
at solar control unit rU.
Natural cooling function
The building can be cooled with heat pump control unit 2 in conjunc-
tion with NC-Box iP (accessories). The natural cooling function is
enabled by control unit 2 as soon as the outside or room temperature
(cooling limit temperature) that can be selected at control unit 2 is
exceeded. Circulation pumps iR and iW in the NC-Box start and 3-
way diverter valve iQ switches to cooling. Heat is now extracted from
the room via heating circuit uP and transferred to the brine circuit via
the plate heat exchanger in the NC-Box. The brine circuit transfers the
heat to the ground via geothermal probe wU. DHW can be heated by
heat pump 1 whilst cooling mode is operational.
3
VIESMANN
67