Viessmann Vitocal 222-G User Manual page 172

Vitocal 200-S/222-S/242-S
5.10 Vitocal 222-S and Vitovent 300-F for supply air and DHW heating in a passive house
ID: 4605497_1304_01
Application range
Passive houses with uniform user patterns, regulated mechanical ven-
tilation with supply air heating and DHW heating.
Main components
■ Vitocal 222-S, type AWT-AC 221.A04 with integral DHW cylinder
and control unit Vitotronic 200, type WO1C
■ One heating circuit without mixer for supply air heating via
Vitovent 300-F, reheater coil and 25 l heating water buffer cylinder
required
Requirements
The minimum flow rate of the heat pump must be safeguarded by sec-
ondary pump 6 and the 25 l heating water buffer cylinder.
Central heating by heat pump
The heat pump starts if the actual temperature captured by the return
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.
Required parameter settings
ID: 4605497_1304_01
Parameter
7000
7D00
7D02
2003
System examples
(cont.)
Value Function
2 With heating circuit A1/HC1, DHW cylinder (delivered condition)
1 Enable Vitovent
1 Enable hydraulic reheater coil
1 Remote control (if installed)
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. Once the actual return temperature value at the return temperature
sensor inside internal unit 1 exceeds the set temperature selected at
the control unit, the heat pump and secondary pump 6 are switched
off.
DHW heating by heat pump
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 the integral cylinder temperature sensor
and the control unit, which controls the integral secondary pump in
conjunction with the integral 3-way diverter valve.
The heat pump raises the flow temperature to the value required for
DHW heating.
The control unit switches the heating flow to the heating circuit via 3-
way diverter valve "Heating/DHW" 5 if the actual temperature at the
upper cylinder temperature sensor exceeds the value set at the control
unit.
The flow temperature can be raised > 60 °C via integral instantaneous
heating water heater 4.
5
VIESMANN
177