Buffer Cylinder Heating - Viessmann VITOTRONIC 200 Service Instructions Manual

Photovoltaics
(cont.)
DHW heating can be brought forward even if the fol-
lowing conditions for DHW heating would not ordinarily
permit it:
■ Temperature condition at the cylinder temperature
sensor is not met: See page 40.
DHW heating is off according to the time program.
■
The DHW cylinder is only heated if it is likely that suffi-
cient power is made available by the PV system.
Heating to set DHW temperature 2
With "Enable own energy consumptn for set DHW
temperature 2 7E10" set to "1", the DHW cylinder is
fully heated to "Set DHW temperature 2 600C" with
power from the photovoltaic system at least every
7 days.
Heating begins if all of the following conditions are
met:
On-site power consumption is enabled (see "Ena-
■
bling on-site power consumption").
■ The electrical energy of the PV system captured by
the energy meter exceeds "Threshold for electrical
power 7E04".
The daily maximum of fed-in electrical power is
■
expected within a short time.

Buffer cylinder heating

The set buffer temperature will be increased by "Raise
set heating water buffer cylinder temp PV 7E22" if
the electrical output of the photovoltaic system
exceeds the "Threshold for electrical power 7E04".
In order to heat the buffer to the higher set buffer tem-
perature the following conditions must be met:
■ Utilisation of power generated on site is enabled:
See "Enabling utilisation of power generated on site".
■ The buffer temperature falls below the higher set buf-
fer temperature by the reduced start hysteresis.
A heat demand for the heating circuits is expected
■
soon. For this forecast, the outside temperature
curve for the previous day is evaluated.
■ In "Time prog buffer cyl" time phase 1 is active for
the next 5 h.
Central heating
"Standard room temperature 2000" or "Reduced
room temperature 2001" are raised by "Raise set
room temperature PV 7E23".
Central heating begins if all of the following conditions
are met:
■ Utilisation of power generated on site is enabled (see
"Enabling utilisation of power generated on site").
There are heat demands from the heating circuits.
■
In "Time program heating" 1 time phase is active.
■
If the heat pump output is not sufficient, the instantane-
ous heating water heater is also switched on with
power from the photovoltaic system.
Heating the DHW cylinder with on-site power ends
when "Set DHW temperature 2 600C" is reached.
Note
If whilst the DHW cylinder is being heated the condi-
tions for on-site power consumption are no longer met
(see "Enabling on-site power consumption"), heating
continues until "Set DHW temperature 2 600C" is
reached. For this, the heat pump and any booster
heaters required are supplied with power from the
mains.
Utilisation of power generated on site for heating the
buffer cylinder ends when the higher set buffer temper-
ature is reached at the secondary circuit return temper-
ature sensor.
Note
The raised set buffer temperature becomes inactive if,
during buffer heating, the conditions for utilisation of
power generated on site are no longer met (see "Ena-
bling utilisation of power generated on site"). Heating
continues until the standard set buffer temperature has
been reached. For this, the heat pump and any boos-
ter heaters required are supplied with power from the
grid.
Central heating with utilisation of power generated on
site stops when there is no more heat demand from
the heating circuits.
Function description
71