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SOLATHERM
reserves the right to modify characteristics of the products or their accessories and components without prior notice.
A solar water heater (SWH) is a system that can provide hot water, using the direct and indirect
solar irradiation. It consists from a storage tank where the sanitary water is stored (secondary
loop) and the solar panel(s) (solar collectors) which, along with the annular heat exchanger of
the storage tank (jacket) and the connection pipes connecting them, constitute the primary
circuit.
Heating of the water in based on a natural principle of hot being lighter and less dense than
cold, therefor by stratification, is always at the highest point while cold always sinks below. This
is why these types of solar systems are referred to as Natural Circulation or Thermosiphon
Systems.
In a Solar Water Heater, the thermal fluid (in the primary circuit) is heated by the sun in the
solar panels, getting lighter, so tends to rise up the solar panels, through the connecting pipes
and inside the heat exchanger, where it transfers the heat (calories) to the sanitary water stored
in the storage tank. While it exchanges heat with the sanitary water, the thermal fluids
temperature is lowered, slowly returning back to normal and regaining weight, thus returns by
gravity back to the solar panels to start the heating cycle all over again.
Principle Diagram
