How does OpenTherm work?
The standard way to control a heating system is to switch the boiler on and off at intervals with On/Off controls. OpenTherm provides more precise control on the boiler through the control of the gas valve. It allows the amount of heat provided by the boiler to be controlled to match the varying demand signal. By reducing the flow temperature to a minimum as it leaves the boiler, the return temperature is kept below the dew point (55 degrees) whenever possible, thus allowing the boiler to operate in condensing mode.