Answer: low temperature radiators are recommended, whether cast iron, steel or aluminum.
A low temperature boiler can only work with suitable radiators (or a heated floor), i.e. low temperature radiators. This is the drawback of this type of boiler: you have to change the entire installation. So, this kind of work is only interesting if you want or need to renovate the installation of your accommodation, or in the case of new construction. Especially since low temperature radiators are more expensive to buy than other more traditional types, at least 100 € each for standard models. The low temperature radiators can be either of cast iron, steel or aluminum. Given the extent of the work to be done, it is probably best to go through a professional. You too, send us your brico question