I had a cheap Greek heater, I had to replace it with the one in question. When it's sunny, it works great, but shouldn't it be like that? When it's cloudy, forget it, I have to turn on the radiator. I'm in the second year.

I changed it this year in April 2022 and after asking the plumber who comes whenever I have an issue, he recommended it to me compared to other brands like Helioakmi, meaning the same liters but more precisely... of course, it is new... it has a 5-year warranty... so far, everything is perfect... if I see anything in the future, I will mention it.