Why does water drip into your car when the air conditioner is on?
The water dripping from your car's air conditioner is condensation; it is a natural byproduct of the cooling process. Warm, moist air from outside your car is drawn into the air conditioner. The evaporator in your air conditioner cools this air, causing the water vapor in the air to condense into liquid water. This water drips off the evaporator and onto the ground.