Operation of a collective solar water heating system

Two types of technology

The sun's rays warm the absorber in the solar collectors installed on the roof. This heat is transferred to a heat transfer fluid via the coil welded onto the absorber. The fluid, heated in this way, is circulated by a pump in a closed circuit of pipes. Gradually, it gives up the heat from the solar collectors to the water contained in the cylinders. This water, heated free of charge by solar energy, will be routed to the collective hot water system's distribution network. There are two ways to achieve this:

Sunoptimo Drainback system


► With the pump stopped, air takes the place of the liquid in the collectors.

► No overheating and therefore no of deterioration of the fluid.

► No technical limits -> Optimum™ Sizing possible.

► Passive protection of the system.

► Low maintenance.


Conventional "Pressurized" system


► With the pump stopped, the liquid remains in the collectors.

► Overheating, the liquid vaporizes and deteriorates with time.

► This overheating limits sizing technically to approximately 40% of the solar fraction.

► High maintenance.



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