Check to see that system ductwork is not disconnected. The '87 wagon I bought from someone had disconnected ductwork that had air blowing behind the dash!

The easiest way to check is to unscrew the glove compartment. Also you can take out the plastic pieces that hold the fabric up under the steering column to check the driver's side.
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'86 244 and '87 245

Comes about when air with X amount of relative humidity touches an object that chills the air, making the water vapor contained in the air condense out onto the cooler object. Same as condensation on a cold drink glass. It's the warm humans in the car that add to the humidity.

Not running Recirc air brings in the colder and therefore dryer outside air. That will help.

Solution? When you kick on the warm air, kick on the A/C at the same time. The moisture will condense out in the air box. Shut off the A/C whenever you like. Here in Humid Houston I enjoy the cool (or warm) dry dry dry air that running heat and a/c provides.

Good Luck,

Bob

:>)

Make sure your "recirculating" feature is not engaged.

Randy