no it wont, I'm an a/c engineer if it has lost its charge which most cars will do, it will need recharged.
Air coming out of vents should be well below 10degree Celsius with seconds of being turned on. Running a system for extra time will not make it work.
An air con regas consists of-
Reclaim any old refrigerant.
Pressure test with Oxygen free nitrogen to ensure no leaks.
Vacuum the system out to remove any moisture.
Recharge system with correct weight of gas.
This is the correct procedure for regassing any a/c system.