Freon release

Do you mean the system is now empty, or just a little leaked out? The system will work normally after losing a little refrigerant. If it is empty, there is a low-pressure cutoff switch that will stop the compressor from running. That is because if the refrigerant had leaked out due to a small leak, the low side could get pumped into a vacuum if the compressor turned on, and that could draw in outside air through that leak. The humidity in the air is harmful to the metal parts in the system. That is why when you buy new AC system parts, they are capped to reduce the amount of time air can get in. It is also why it is necessary to pump the system into a vacuum for at least half an hour, right before pumping in the new refrigerant. Water boils at 77 degrees in a vacuum. That makes it easy to draw that moisture out.

Mr. Compressor (rather within the system) has a low pressure switch which prevents the system from working should the pressure drop too low.

If it won't come on this may be the reason.

If is still working, but lacks in cooling, you may need to have some added.

The Medic