ModVSol L regulation : how to wire? How to adjust the flow?


As a reminder, (as summarized in this article) whatever your hardware, the steps to commission a pressurized system with Dualsun SPRING panels are as follows:

  • Filling with water

  • Glycol filling

  • Pressure adjustment

  • Flow adjustment

  • Setting the back-up


Regulation wiring

The solar circulator (R1), the lower tank temperature sensor (S2) and the regulation power supply are pre-wired.

The panel outlet temperature sensor (S1) must be connected to terminal S1 and ground as shown in the following diagram.




The electrical connection diagram and the hydraulic diagram are taken from the ModvSol regulation user manual.


Flow adjustment

  • Remove the flexible pipes from the solar station

  • Place the adjustment valve on the flow meter in a vertical position


The pump group is now ready for flow adjustment. To check the flow rate please check the technical documentation of your control group.t.

The flow adjustment is carried out in two stages.

  1. Changing the circulation speed of the pump

It is important to reduce the circulation speed of the pump to improve its life. For this, it is necessary to force circulation.

For that :

  • Press the left control button

  • Select menu “6. Specific functions”



  • Sélect menu “6.3. Régul. de la vitesse R1”

  • Sélect menu “6.3.4.Vit. max.” update value to 70%.


  1. Flow reduction using the flow meter needle

Once the circulation speed has been reduced using the regulation, it is necessary to carry out a finer adjustment of the flow by closing the ball valve of the flow meter. The latter activates a valve that will reduce the flow. The flow rate is read on the lower edge of the float.



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