ᐅ Solar Pump Wilostar Single-Family Home Settings – 3 Levels?!

Hello.
In our single-family home, the Wilostar solar pump is set to level 3.
I asked the builder if this setting was correct, but he couldn’t answer.
Surprising...
So now I’m looking for information here myself.
The pump has 3 levels. Currently set to 3.
The solar system only supplies the domestic hot water storage tank, not the heating system!

What do the 3 levels do?
Does level 1 mean the solar heat transfer fluid is pumped slower?
And levels 2 and 3 mean faster flow rates?

In very hot conditions for the solar fluid (mid-summer), would it be better to have a faster or slower flow?
Probably level 3 in summer and level 1 (eco) in autumn/spring?

Or how can this be explained more clearly?

Thank you.

Yes, you understood correctly. If you enjoy it, you can adjust it twice a year; otherwise, just leave it at level 3 and that’s fine. The pump should only run when there is sunlight and energy yields are expected.