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heat so that it can be used to heat domestic hot water or for
additional heating.
whose main component is a selectively-coated absorber.
The heat is pumped via a closed piping system, the solar circuit,
from the collector to the storage tank. The solar system not only
provides hot water in the summer and in transitional periods,
but can also even provide some in winter. A frost-resistant
mixture of water and glycol is used to prevent the heat-transfer
fluid freezing in the solar circuit.
of heat from the collector to the storage tank. The controller
always starts the circulation pump of the solar circuit when the
temperature in the collector is several degrees warmer than the
temperature at the bottom of the storage tank. This transports
the solar fluid from the collector to the lower heat exchanger,
where the heat is transferred to the drinking water in the storage
tank via the solar circuit heat exchanger. The cooled solar fluid
then flows back to the collector in the return pipes.
is stratified in the storage tank according to its density or
temperature: The hottest water is at the top (where it is drawn
off), the coldest water is at the bottom (where cold water is fed in).
With the current standard system size for one to two family houses
(approx. 1.0 to 1.5 mē collector surface per person and approx.
80-100 l storage tank volume), the drinking water in summer is
primarily heated by the solar system. This results in an annual
solar coverage (percentage of the total energy requirement for
heating drinking water provided by solar energy) of approx.
60 percent. The remaining 40 percent must be covered by
additional heating. This is generally performed by a solid fuel
and the upper reheating heat exchanger of the storage tank.
You can select a tailor-made controller from the Steca solar
thermal controller product family based entirely on the
requirements of your solar system. A range of monitoring and
control functions guarantee that your solar system runs
safely and maximise its service life.