[NeilTruter]

I have noticed that the air from the vents are still warm compared to the air from the open windows even with the temp control set all the way to the left (blue portion) of the dial. (aircon switched of, fan on slow).
Is this normal or might it be possible that old Betty's heater doesnt close all the way?
My astra gives me almost the same as outside air in similar conditions.

[paw_by_paw]

Check your heater system it might solve your problem or maybe an blockage in the fan itself or somewhere in the system, You perhaps have small kids? I have found many years ago my kids stuffed strange stuff into air vents and caused havoc with the system.