Fogging on the windshield when the air conditioning is on inside the car is mainly due to the significant temperature difference between the inside and outside of the glass. Here are specific solutions to address windshield fogging when using the air conditioning: 1. Open the windows: When the fog is not too heavy, you can appropriately open both windows to allow air circulation, which eliminates the temperature difference on both sides of the windshield and naturally prevents fog formation. Alternatively, turning on the cold air from the air conditioning can quickly remove the fog. Both methods work fast, but their downside is that they are not suitable for prolonged use in cold weather or during rain or snow. 2. Use the blower: Blowing cold air provides a quick but temporary solution, while blowing hot air can fundamentally solve the fogging issue. Fog will not reappear after turning off the hot air, nor will it make the car uncomfortably cold in winter. However, the main drawback of using hot air is its slow effect, requiring a long wait to see results. Additionally, running the heater while driving consumes more fuel, making it a bit costly. 3. Use a defogging spray: The principle of defogging spray is simple—spraying a layer on the windshield forms a protective film that prevents water vapor condensation. However, this protective film has a short lifespan and requires frequent reapplication to maintain its effectiveness.
