System Example 3 - Viessmann VITOSOIC 100 Installation And Service Instructions Manual

Preparing for installation

System example 3

Vitodens – DHW heating with freshwater module and central
heating backup with heating water buffer cylinder
Main components
■ Viessmann solar collectors
■ Freshwater module
■ Heating water buffer cylinder
Vitocell140-E or Vitocell 160-E
■ Vitosolic 100, type SD1
■ Solar-Divicon
■ Wall mounted gas boiler from the year
of manufacture 2008
– Vitodens 200-W, type WB2B
– Vitodens 300-W, type WB3C
Function description
Freshwater module qP heats DHW
when hot water is drawn. The energy
supply to freshwater module qP is pro-
vided via heating water buffer cylin-
der rP. Buffer cylinder rP is heated by
the solar thermal system or, in the upper
area, by boiler 1.
The heated DHW is heated by freshwa-
ter module qP according to the instanta-
neous water heater principle. An internal
pump transports the heating water from
heating water buffer cylinder rP into the
freshwater module qP. This heats the
DHW in the heat exchanger of the fresh-
water module qP according to the coun-
tercurrent principle. The freshwater
module qP is regulated by its internal
control unit.
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When utilising the freshwater module
with integral DHW circulation pump, the
three-way diverter valve qQ in conjunc-
tion with sensors S3 qE and S4 qW of the
freshwater module qP can be regulated
by its control unit to provide an optimum
stratification of the return water into the
heating water buffer cylinder rP.
DHW heating with solar energy
Solar circuit pump R1 eE starts and
heating water buffer cylinder rP is
heated up if the temperature differential
between collector temperature sensor
S1 eQ and cylinder temperature sensor
S2 rQ exceeds the start temperature dif-
ferential DT E.
Solar circuit pump R1 eE stops if:
■ The actual temperature falls below the
stop temperature differential DT A
■ The electronic temperature limit of
control unit eZ is exceeded (max.
90°C)
■ The temperature selected at high limit
safety cut-out rR (if installed) is
reached
Entire heating water buffer cylinderrP is
heated by the solar thermal system if the
insolation is adequate.
The upper part of heating water buffer
cylinder rP will only be reheated by
boiler 1 if the actual water temperature
falls below the set temperature selected
at boiler control unit 2.