Warm air from air vents even set to low temperature and source set to be from outside.

My car blows a warm air from air vents it feels like a hairdryer even if I pit the temperature on lowest level and put the air source to be from outside it only does when I restart my engine, doesn't come when I first start my engine and the only way to cool it down is to turn the AC on.
But without AC it doesn't not get cool, it feels like hairdryer, and it's unbearable, it will be so great if you could tell me solution.
Many thanks.