After second evolution of four way valve reconstruction scheme it meet my expectations. Fluently regulate throw whole valve handler angle range.

It is fanny but most pipe diagramm on public internet are wrong. It is working but far away from optimal.

For example like this:

Because pump at could way to boiler. (čerpadlo kotle)

Much more better is to make separate circuit "boiler - pump - boiler" which make boiler output and input on similar temperature. What is best for boiler performance. Four way valve "input" is in parallel to boiler and building side is connected to "output" side of fourway include second pump. If somebody interested I can draw some picture of it.

Hot water boiler is simply in paralel to main boiler without any additional equipment. Have to be in the middle between hot and could pipe of the main boiler, means altitude. (in my case it is)

Now I can start with regulation SW! Hu Hu