996 fan heater not working

[enzo996]

Hi, I hope somebody can help.I have just bought myself a 1998 996 Carrera S. The fan heater only works on initial starting of the engine from cold and will continue to work all the time the car is running. The problem occurs when I turn off the engine and then start the engine up again the fan heater doesn't work. The controls on the dash all work fine but no air blows, hot or cold. Any ideas, I don't want to get fleeced at a dealership or specialist.Thanks Enzo996