Originally Posted by StephenVA

Nothing will better than some cool air.

A little background on what is happening to your X:
Under your dash inside of the ducts is a small radiator looking part that has air flowing through it (inside or outside air depending on the HVAC controls) which has freon (134A actually, as Freon is a DuPont brand name for the old R12 stuff). As the refrigerant expands through the valve under pressure it's temp is lowered, as the air travels through the mini rad, the heat from the air is transferred to the freon. If the pressure is too low for the freon to circulate correctly, moisture builds up forming ice until no air will travel through- hence no air from the vents. You probably noticed a white vapor coming out of the vents frequently especially just before the air flow slowed down. All of that ice melts off when you let the vehicle sit for a few hours.

Bottom line: Add some freon as you did, enjoy the cool air and when you are ready any A/C competent shop can hang a few gauges on the system, read the internal pressures, evacuate the system, checking for leaks and determine where the issue(s) are as this system is SEALED> meaning one continuous loop with no openings. I would recommend a BMW independent shop as they will be familiar with our unique twist to HVAC systems and they will have the necessary skills and tools to find leaks quickly. The freon gas has to be leaking somewhere> Hoses, fittings, evaporator, condenser, or other failed parts. Could be something simple such as a failed low pressure switch, Receiver dryer, or something big. Better to find out soon and have it repaired as summer is here! Don't forget that big rad up front has a A/C condenser in there too which can be blocked by road trash, leaves, and subject to hits from the stuff we don't swerve around.

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