Could be a dirty filter causing lack of airflow, High pressure switch tripped, compressor failure, refrigerant loss. You'll need to open the unit and tun it on and see if you are getting power to your compressor with a meter. If you are and it is not working, your compressor has failed. If your not, you'll need to look at the wiring diagram and follow the line that powers your compressor and check the safety's that control it to see which one is open.
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Could be a dirty filter causing lack of airflow, High pressure switch tripped, compressor failure, refrigerant loss. You'll need to open the unit and tun it on and see if you are getting power to your compressor with a meter. If you are and it is not working, your compressor has failed. If your not, you'll need to look at the wiring diagram and follow the line that powers your compressor and check the safety's that control it to see which one is open.