Красота!!!

The main difference between this type of bath and the previous one is the absence of a chimney in the stove. When the stove is heated, the smoke does not escape from the room to the outside, but remains inside, warming it up. As a result, the internal surfaces of the steam room become covered with black soot and soot. This is where the name came from.
Don't they know this in rusia?

А почему по-черному? Вон труба, дым в трубу выходит)