Defogging with Hot or Cold Air in Cars?

[Catalina]

Car windows fog up due to the significant temperature difference between the inside and outside of the vehicle. To eliminate fogging, drivers can use either cold or hot air to achieve defogging effects. Below are methods for choosing between cold and hot air defogging: 1. Defogging with cold air: Turn on the air conditioning's cold air, press the A/C button, adjust the vent direction to blow toward the windshield, and set the fan speed to maximum. This reduces the temperature difference between the inside and outside of the windshield, making it harder for fog to form and effectively eliminating it. This method is suitable for quick emergency defogging. 2. Defogging with hot air: In winter, using warm air for defogging is more comfortable. Although hot air takes longer to defog compared to cold air, it prevents the windshield from fogging up again.