Chevrolet: No heat inside car, chev lumina, problum

Question
I have a 1992 chev lumina sedan 3.1L system has been flushed thermostat replaced heater core replaced car heats up hoses get hot but no heat blows inside of car.push buttons and the doors change from vents to floor to defrost switch from hot to cold setting and you feel a change in air temp. what could be the possible cause it has to bleeder screws and i have bled them both several times and still no change please help...........

Answer
hi,
  no heat, I hope it is not that cold where you are,
the only thing that i can think of is the switch could be bad and if you have a vacume s/w a hose could be off or broken or the door / vent that opens to let the heat is closed that is where the problum is .if you can open it manualy it should work,
I hope you get it open it is getting cold out.
good luck
bigw45