@Bilal
if it is country specific thing, then I would have to say I am not sure but the cars we have here which have the temp controlled by the knob and by taking it to the red zone will activite the heater, there is not doubt about that.
What you are saying is that if you take it to the red zone there will be a mixture of air from the vents, ie. if the ac button is pushed on. That is true, agreed to that. But what I am saying dose not involve the red zone on the knob. I am saying you can control the activation of the compressor from the knob within the blue zone, and guess what I just did that when I went out and came back. The if I leave it in the blue the compressor would get activated and switched off on a predetermined setting from the factory. but once I raised the knob to a lower temp blue zone. The compressor got activated and then it would switch off for a while longer then the previous setting, and switched on again when I noticed the temp was bit warmer. But in this process at no time the heater is activated unless it is in the red zone.
That is what I am trying to say here. So if you have a lower optioned cars in Pakistan being made just to save cost, then I say what you are saying would be right.