eta 13180LP-T, Operation

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ETAtouch controller [Solar] function block
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5.8.2 Solar heating system with 2 tanks
Switching between several tanks
If the solar heating system charges several tanks (for
example, buffer and hot water tanks) it will switch
between tanks on the basis of the currently set
priorities. The tank with the highest priority is charged
first.
Fig. 5-75: Solar heating system for the buffer and hot water
tank
If the solar power is not sufficient for charging the tank
with the highest priority (collector is only warmer by the
difference [Switch-off diff.] than the tank that currently
requires charging), the tank with the next highest
priority is charged after the minimum time has elapsed
(factory setting 20 minutes).
If the solar power increases once more, after the
minimum time has elapsed solar charging switches
back to the tank with the higher priority. This ensures
that the tank with the highest priority is always charged
first.
Uniform charging of tanks without consideration
of individual priorities is also possible. The
[Service] permission is required for this. Then you can
use the [Changeover if diff. >] parameter in the solar
heating system text menu to configure the temperature
difference between the tanks.
5.8.3 Solar heating system for buffer with
2 internal coils
Switching between two internal coils
When switching between two internal coils, charging is
defined in two different areas of the buffer. The
purpose is to produce a sufficiently high temperature in
the top part of the buffer, so that the boiler does not
have to start for hot water charging.
Fig. 5-76: Solar heating system with switching between two
coils at the buffer
The solar pump starts as soon as the panel is warmer
than the current temperature in the upper buffer area.
Depending on whether the "Buffer" or "Buffer-
Flex" function block was installed, the switching
differs between the two coils.
For "Buffer" function block:
An internal target temperature [Buffer target solar] is
provided to control the switching. The target
temperature is determined by referencing current re-
quirements or minimum temperatures and can be
viewed in the buffer's text menu under:
Tab. 5-1: "Buffer" function block
The conditions for solar charging into the upper buffer
coil are:
• The buffer is not currently being charged from the
boiler.
• The outside temperature is above the set minimum
temperature of 10 °C ([Min. out. temp. Solar prio.]).
• The temperature in the upper buffer area is lower
than the target temperature [Buffer target solar].
Buffer
Buffer top Solar
Buffer target solar