Vaillant VR 68, Руководство по эксплуатации и установке, Страница: 24 / 29

23 Operating and Installation Manual for Solar Module VR 68 0020054784_00
8 VRC 430/VRC 430f Operation
level for the operator
The operating level for the operator serves to indicate
and to adjust/modify the basic parameters. The setting/
changing of parameters can be carried out by the user
without any special previous knowledge and during
normal operation.
The parameters are shown in various display screens in
the display area of the controller VRC 430 or VRC 430f.
The operating concept is described in the operating and
installation instructions of the controller VRC 430 or
VRC 430f.
The installation of the VR 68 solar module in the solar
heating system results in a change to the standard
configuration as described in the manual for the
VRC 430 or VRC 430f; the addition of
display screen 13 :
Solar gain
13
Solar gain 1720 kWh
Reset solar gain? no
> Reset sola gain?
Fig. 8.1 Display screen 13 Solar yield
The current solar yield which has accumulated (in kWh)
since the last time the system was reset to the initial
value of 0 kWh is displayed.
The solar yield can be reset to 0 at any time.
8.1 Optimising the solar yield
By using the solar energy from the sun which is free of
charge you are taking care of the environment and
reducing your energy costs. The solar energy is used to
heat the solar cylinder (e.g. solar hot water cylinder).
The corresponding energy savings are expressed as the
solar yield in kilowatt-hours.
If the temperature differential between the solar
collector and the lower section of the solar hot water
cylinder is greater than a defined value, the solar pump
is switched on and thermal energy is transferred to the
drinking water in the cylinder. The solar yield is limited
by the maximum temperature of the cylinder and the
solar circuit protection function. These are designed to
prevent overheating of the solar cylinder or solar circuit.
If insufficient energy is obtained from the sun, the solar
hot water cylinder is reheated via the boiler. The
reheating process is enabled with reference to the hot
water target value and the time window for hot water. If
the temperature in the upper section of the solar hot
water cylinder falls to 5 °C below the hot water target
value, the boiler is switched on and the drinking water in
the cylinder is heated up until the desired hot water
target value is reached; the boiler that provides energy
for reheating is then switched off. Reheating by the
boiler only takes place inside the programmed time
window for hot water. A number of methods can be used
to optimise the solar yield, these are described below.
8.1.1 Optimisation at the operation level
for the operator
The control system for the generation of hot water is
dependent on the specified hot water target value and
the programmed time windows which is why these
parameters are used as the basis for optimising the
solar yield.
The following measures can be taken at the operation
level for the operator to optimise the solar yield:
- optimise the time window for water heating,
- reduce the hot water target value.
Optimising the time window for hot water generation
Time windows can be programmed for the hot water
generation. The hot water can be heated by the boiler
within a specified time window if the temperature of
the hot water falls by 5 °C below the target value.
This post-heating function guarantees that your hot
water will always be at a comforTable temperature.
Solar energy is exclusively used outside this time
window to heat the water free of charge (providing
sufficient sunlight is available).
h
Note
If the sky is cloudy this may lead to reduced
comfort.
The collector supplies most of the solar energy
when exposed to direct sunlight. Only a small
amount of solar energy can be supplied in
cloudy conditions.
Optimise the time window.
You can make all necessary adjustments at the
controller for your heating system in display screen 4
"Hot water timer programs". Relevant detailed
information is provided in the operating manual for the
controller.
Reducing the hot water target value.
If the temperature falls by 5 °C below the hot water
target value within the programmed time window, the
boiler is switched on to heat up the drinking water.
The boiler switches off once the hot water target
temperature has been reached.
VRC 430/VRC 430f Operation level for the operator 8