Regulation is working as I would like. Remain small problem is could start optimalization. System is starting longer time than possible speed for rooms warm up.

Finally I used regulation with main heating temperature setup with big corrections depend on in/out radiators temperature difference which is slightly different from initial idea. Reason is system stability and more easy full power mode.

I add servo (regulation) speed possibilities Up, FastUp, VeryFastUp as wel as Down, Fast Down in programm to make change speed progressive. Other problem solved is temperature time response of boiler and radiators. Regulation must work in same time range. It is important for regulation loop stability.

It is working fine now. Only remain things are to add to web interface heating current temperature setup (with correction) and could start up improvement.

Becouse not typical heating use (weekend heating only) I still working on remote ESP8266 thermometer to measure some room to know if minimum temperature to reach. Untill minimum temperature reached, heating should work in full power mode without regulation and hot water warming. It is important for quick room temperature restore after some day without heating.