3- Sometimes NO Air or A/C come out from the centre,only from the sides when accelerating. When accelerator was released, air started to flow. ...

I have the same problem in my car and i went to a workshop where he started try and error, and after waiting for 3 hours he was not able to repair it. Is there anything i can check myself to fix this problem, it is a real problem since i'm living in Dubai and the temp is 45cel.

Thanks ...