Well just driven 1 junction up the motorway at 32'C on the heater, needle stayed put 12'oclock. The heat pumping out of the vents now is immense, it burns!
Will be taking this into the dealers on Wednesday. Took him an hour in the end, bleeding etc! But actual thermostat took 20 mins, hardly a lot for the dealer to check. Alls he did was do a like for like comparison. Mine was broke, not rocket science