What is the expansion volume of the heat exchanger of the SPRING panel and the DualQuickFit hose?



With its aluminum exchanger, the SPRING4 expansion is negligible. Therefore there is no sense to calculate it. 


At +20°C the polypropylene heat exchanger of the SPRING3 panel has a volume of 5 liters. 

Neglecting the expansion in thickness (small dimension) we obtain the following results : 

  • At -20°C, i.e. a negative differential of 40°C compared to 20°C : the exchanger contracts and reduces its volume by 1.2% to reach 4.94L.

  • At +70°C,  i.e. a positive differential of 50°C compared to 20°C : the exchanger expands and increases its volume by 1.5% to reach 5.08L.

As far as the DualQuickFit® flexible hoses are concerned, we can consider that the diameter remains unchanged because of the small thickness of the skin. However, there will be a slight variation in length : 

  • At -20°C, the DualQuickFit® hose will reduce its length by 0,6%

  • At +70°C, the DualQuickFit® hose will increase its length by 0,8%

To go further : What are the components of a Dualsun SPRING panel?