What is OpenTherm?
OpenTherm is communication protocol for Heating, Ventilation and Air Conditioning (HVAC) systems. Most often it is used in communication between a central heating boiler and a room thermostat. OpenTherm protocol is designed to control modulating heating appliances which allows to reach better efficiency and energy saving. It is simple but powerfull protocol with large set of commands which enable the manufacturer to build extra functions into their control devices. Check OpenTherm protocol specification v2.2 for more details.