Hi,
I'm simulating solar assisted heating with underfloor heating (set temp. 40C). I want to investigate the influence of solar collector connections in the array (number of parallel and serial) in regard of solar fraction.
When I compare for example 32m2 with 4 in serial (flow rate 800 kg/h) I get lower solar fraction compared with 32 m2 with 2 in serial (flow rate 1600 kg/h), even I get that the maximum solar fraction I can achieve if all 32 m2 (flow 3200 kg/h) are connected in parallel.
Only if I increase the flow rate at the serial connection then I get bigger solar fraction.
I use solar collector Type 539 and tank Type 60 with internal heat exchanger
Does have someone experience(explanation) regarding this kind of issue?
Kind regards
Martin