Are Dualsun home heating (SCS) compatible with Dualsun panels?


The Dualsun hybrid solar panels can participate in the heating of a house on sunny days: we speak in this case of installations called "Solar Combined System" (or SCS). 

As its name suggests, it is a combination of a solar panel heating system on days when there is enough sunshine, and a non-solar heating system for the other days (oil, gas, wood boiler or heat pump).  


Connection diagram for the heating of a house in a "Combined Solar System" with solar panels


Ra: Solar circulation pump controlled by Dualsun SLL solar controller relay (R1)
Rb: Heating device relay controlled by Dualsun SLL solar controller relay (R2 or R4)


The Dualsun "SLL" controller visible on this diagram allows to control the solar combined heating system whether it is a Heat Pump, a boiler or an electrical resistance via a secondary power relay (R2) or a potential free relay (R4). This is in order to optimize the solar production by inhibiting the activation of the auxiliary heating when the free calories of the solar energy are exploitable.
More information on the advantages of Dualsun SLL controller over pressurized systems.


We recommend installing at least 10 Dualsun SPRING solar panels (compared to 4 to 6 for domestic hot water only) because heating is a winter requirement, the season when there is the least amount of sunshine. 


It is important to note that :

  •  the more the heating emitters in the house are at "low temperature" (underfloor heating in particular), the better the performance of the SCS system will be since the temperature of the solar storage tank will be lower with this type of emitters and therefore more easily reached by the solar panels.

  • If the house is equipped with high-temperature radiators, the overall performance of the SCS system will be lower.  

It should also be noted that the solar contribution of DualSun will be even better in the inter-season (fall/spring) than in the middle of winter, where the boiler will be essential for the proper functioning of the system.


In case the boiler also needs to be replaced, it may also be interesting to use fully integrated coupling solutions (3-in-1: Electricity / DHW / Heating) such as for example : 

  • Our Dualsun panel/heat pump coupling offer Daikin ECH2O Sun

  • Our combined offer Dualsun panels / ÖkoFEN Wood Boiler Smart XS-e Dual