Which Button is for Defogging the Air Conditioning?
2 Answers
Air conditioning defogging is indicated by a fan-shaped pattern on the front windshield, accompanied by three upward floating lines. A rectangular frame symbol represents defogging and defrosting for the rear window. Below is some knowledge about air conditioning defogging. Physical Principle of Hot Air Defogging: When gas containing fog mist flows through the defogger at a certain speed, due to the inertia of the gas, the liquid droplets aggregated by the collision between the fog and the wave plate are large. The gravity generated by the droplets exceeds the combined force of gas lift and liquid surface tension, causing the droplets to separate from the surface of the wave plate. Physical Principle of Cold Air: After the liquid refrigerant absorbs the heat of the cooled object in the evaporator, it vaporizes into low-temperature and low-pressure steam, which is then sucked in by the compressor, compressed into high-temperature and high-pressure steam, and discharged into the condenser.
When I first started learning to drive, fogged-up windows were a real headache. The defogger button is essentially one with a windshield icon on the dashboard's air conditioning control panel, usually accompanied by symbols of heat or airflow. Pressing it automatically cranks up the fan to high speed, directing strong airflow onto the front windshield to clear fog. I often see friends use this button immediately when getting in the car on rainy days or mornings—it works incredibly fast, putting safety first. If you can't locate it, check the car manual; positions are generally similar. In newer cars, it might be integrated into the central touchscreen's AC interface, where a manual tap makes it convenient. Make it a habit to press it whenever needed while driving—clearing fog ensures better visibility and prevents accidents. Remember to pair it with the heat mode, especially effective in cold weather when fogging is worse; don’t let insufficient airflow delay things. Also, some cars have a separate rectangular button for rear-window defogging, featuring heating wires—don’t mix them up. The operation is simple but crucial, particularly for beginners who should practice a few times to memorize its location.
