Bit of a strange one this !
Down stairs on our house we have 3 double convector rads. Only one panel on each radiator of all 3 is getting hot. All the double panels upstairs are hot both sides. Downstairs, one side is bouncing hot but the other side is stone cold freezing. There is no air in the system, no leaks either.
The boiler is a worecester and is working perfectly well.
Does anyone have any clues as to what this could be ? Very strange how its just one side.... :?