It is quite big. https://maps.gstatic.com/m/streetview/?panoid=bmmDM51FRh97VUlN4EKUGQ&cbp=0,99.07875786595795,,0,0
From that website boiler should be spot on. Managed to get average radiator to 54 degrees using an infra red thermometer at the top middle of each radiator.
They are all very...