Which heat transfer fluid should be used in a pressurized system?
For a pressurized installation, do not use water from the municipal distribution system, as it contains chlorine which causes corrosion of metals and therefore of the heat exchanger of the panel (in the case of the Wave panel only), as well as the metal parts of the solar circuit in the machine room (copper fitting, brass, valves, the exchanger tank, etc). The use of mains water in the closed circuit can accelerate the formation of sludge in the circuit.
The heat transfer fluid must be a mixture of glycol and demineralized water. We cannot guarantee an installation that has not been commissioned with demineralized water.
Consequently we recommend using a pre-mixed glycol solution, which already contains demineralized water as well as antioxidants.
The percentage of glycol contained in the heat transfer fluid varies depending on the region. In France, it is required by law that the installer comply with the requirements of ENN1991 1-6 clause 220.127.116.11, which indicates the minimum temperature to be taken into account.