Mine has just stopped working too....since the alarm was installed.
Remove the console, and on the temperature slidy thing there are TWO rods - I found that there was only ONE connected to the slidy thing on mine, so the engineer is coming (or I will do it my self

) to repair it....
Thats a first idea!
***IGNORE ABOVE*** Clifford engineer punched a hole in the coolant line in the car which is why there is not hot air coming out....could you have an air bubble in the system?
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