Dash vents not working

End of last summer the dome light in my 96 Lumina was left on for several days. Battery died, had to be charged overnight. Ever since the battery died, my car now chugs and my dash vents are no longer working. I bought the car used, and he mentioned something about the vents not working, but he had his boys fix it. It is now impossible to find out what he had them do to fix it. I really need my a/c! The little bit of air flow that trickles out of the defrost and floor vents is no where near enough to cool the car :( Its the same for fan, heat & a/c