Are Dualsun SPRING panels compatible with Ökofen pellet boiler?



Yes ! Dualsun has partnered with ÖkoFEN to present the Smart XS-e Dual: a joint system that combines ÖkoFEN’s Smart XS wood pellet boiler with DualSun Spring panels. This offer allows you to completely cover your heating and hot water needs with one unique system that is 100% renewable.

Smart XS-eDual® - How it works

A special controller integrated in the boiler manages perfectly the solar and wood combination by prioritizing the solar production :


  • From November to April,
    the Smart XS takes over for the hot water as the Spring panels will not generate enough during the winter months, and covers heating needs as well.

    The cost of wood pellets, cheaper than electricity or other heating fuels, will provide savings with a renewable source.

  • From May to October,
    the domestic hot water is covered by the solar panels and the Smart XS boiler is shut off.

    Thus the Smart XS will be used less and its lifetime will be extended.


How to adjust Dualsun controller coupled with Okofen pellet boiler? 

The flow rate setting of the Dualsun solar controller does not depend on the auxiliary system.

The Smart XS controller of the Ökofen boiler manages the solar energy natively. The specific documentation for the Smart XS-e Dual offer provided by Ökofen includes the Dualsun recommendations.

The same control system manages the solar / DHW and heating priority to guarantee optimal operation of the system.


Indeed, a Dualsun solar system allows to heat or pre-heat domestic hot water. However, depending on the solar contribution and/or the hot water consumption, it is always necessary to couple an additional solution with electric, gas, wood or other energy to cover all the needs.


The flow rate setting of the solar station is directly dependent on the sunshine conditions and the hot water temperature in the solar storage tank.
To find out the flow rate setting of Dualsun systems according to the application.


  • The solar circulation pump management system allows the flow rate to be modulated according to the solar energy received and to be returned.

  • In order to optimize energy savings, the coupling gives priority to the solar thermal system to raise the water temperature.

  • The additional solar energy is used to supplement - or provide in case of insufficient solar energy - the energy input necessary to cover the need.