What material is used for the Spring panel heat exchanger?
The heat exchanger of the Spring panels is made of PolyPropylene (more precisely we use a Block-Copolymer).
On the one hand, this material has been designed and tested to last 40 years in solar heating applications, which has been confirmed by a theoretical ageing study carried out by the CNRS PIMM laboratory, as well as by accelerated ageing tests at TÜV Rheinland.
On the other hand, this material has already been used for decades in similar types of applications.
For example, there are already thermal collectors for swimming pool heating that have been using the same material as the DualSun SPRING exchanger for decades.
That said, the DualSun exchanger is much more protected than a pool heating collector, so its longevity will be greater:
- The exchanger is positioned behind the photovoltaic laminate which constitutes a very effective anti-UV barrier (glass, EVA, backsheet, etc.).
- The temperatures in the DualSun SPRING exchanger are limited by the photovoltaic system, which also recovers energy. The DualSun heat exchanger thus achieves a lower stagnation temperature than the exchanger in full sunlight without PV laminate,
- Our recommendations on pressure are clear: if the panel does not exceed 1.5 bar in operation it will have an exceptional longevity.