I have no heat on 1999 Hyundai Elantra

My car has no heat. I had perfect heat one day, than I shut the car off for about 2 hours than turned it back on and no heat. The blower is working, however just blowing out cold air. We have replaced the thermastate and my car is NOT over heating. I have been told it could be the heater core. But there is no anti-freeze smell when you turn the heat on, or there is no leakage inside or out of the car nor is there any condensation on the windows. Not sure what else to check. Please help!!

1 answer
check to see if the blend door inside of the car is moving , when you turn it from hot to cold , there is a door in the heater box that should move accordingly