[svenrico]

Originally Posted by SV650rules

Room thermostat is independent of boiler flow temperature, there is a control on the boiler itself to regulate how hot the boiler gets the water before it starts to lower the gas flames ( modulation ).

https://www.diynot.com/diy/threads/c...rn-temp.38438/

As a householder I don't expect to touch anything on the boiler, British Gas service it once a year and I adjust the heat coming off the radiators by the hall thermostat and TRV's on the radiators.