What is the maximum allowable flow rate of Dualsun panels?


To determine the maximum allowable flow rate of Dualsun Spring hybrid panels, we distinguish two types of installations:

  • Direct pool systems
    Maximum allowable flow rate = 400 L/h/panel

  • Pressurized systems
    The question of the maximum allowable flow rate of Dualsun Spring hybrid solar panels arises mainly at the time of hydraulic commissioning in pressurized systems.

Indeed, it is very important to properly purge the air trapped in the hydraulic circuit when filling the system to ensure proper operation of the system. This is to avoid cavitation of the hydraulic circulation pump.

To properly bleed the air at the time of filling, we speak rather of minimum flow:

  • 200 L/h/panel in portrait

  • 250 L/h/panel in landscape

These flow rates may be exceeded as long as the inlet pressure at the panels does not exceed 2 bar, and only for the time required to bleed the air.

The number of panels that can be connected together in one string is limited to 6 in order not to exceed this filling pressure.

The final filling pressure must be adjusted so that the pressure in the panels does not exceed 1.5 bar.

Reminder: The control pressure by the operator when filling is the pressure displayed on the system pressure gauge. Therefore, it is necessary to take into account the manometric head of the installation.


Filling pressure for venting:

P = 2 + Hinstallation/10 [bar] 


Final filling pressure:

P = 1.5 + Hinstallation/10 [bar]