Defogging in Winter: Use Cold Air or Warm Air?
2 Answers
When defogging in winter, you should use warm air as cold air can affect comfort. After turning on the warm air, it is recommended to activate the external circulation mode for faster defogging. To speed up the defogging process, you can slightly lower the windows or open the sunroof a bit. For defogging the front windshield, the air conditioning must be turned on, while the rear windshield does not require the air conditioning to be activated—it is equipped with heating wires that can defog the glass when turned on. In summer, cold air can be used for defogging inside the car. When using the cooling function, press the AC button, which is the switch for the car's air conditioning cooling system. Pressing the AC button engages the compressor clutch, causing the engine to drive the compressor. During operation, the compressor continuously compresses the refrigerant and delivers it to the evaporator. The refrigerant expands and absorbs heat inside the evaporator, cooling it. The cooled evaporator then chills the air blown by the fan, allowing the car's air vents to release cold air for defogging.
I've been driving for nearly twenty years, and defogging in winter is a big issue—it seriously affects visibility and safety. The first thing I do after getting in the car is turn on the AC cold air and adjust the airflow to the front windshield. Cold air absorbs moisture quickly, clearing the fog in just a few minutes because it draws out the humidity from inside the car. Once the fog is gone, I switch to warm air to maintain a comfortable temperature—this keeps things both clear and cozy. Remember, never start with warm air right away, as it carries moisture and can actually worsen the fogging, making visibility dangerously blurry. Also, don’t forget to turn on the recirculation mode to bring in dry air from outside. Dirty windows fog up more often, so I regularly clean the interior glass with a microfiber cloth to remove grease and grime. Driving safety is paramount, and quick defogging can be a lifesaver.
