Should You Use Cold or Hot Air to Defog Your Car in Winter?
2 Answers
In winter, both cold and hot air can be used to defog your car. The method for using cold air involves turning on the air conditioning's cold air, pressing the AC button, and adjusting the vents to blow toward the windshield. For hot air defogging, start by turning on the external circulation, wait a few minutes, then switch to internal circulation mode. The car's air conditioning is a crucial comfort feature, capable of both cooling and heating. If using cold air to defog, it's recommended to set the air circulation mode to external to facilitate air exchange between the inside and outside of the car, reducing the temperature difference. Hot air defogging is more comfortable, though it takes longer than cold air, but it prevents the windshield from fogging up again.
Regarding the issue of car defogging in winter, I recommend using the heater as a more practical solution. Fogging occurs due to high humidity inside the car, which condenses on the cold glass. The hot air can quickly heat the glass surface and evaporate the moisture. With decades of driving experience, I've found that initially turning on the A/C button (cold air) for dehumidification works quickly, but don't keep it on for too long, as it makes the interior chilly and wastes fuel. Switching to the heater for maintenance is sufficient. Remember to increase the airflow towards the windshield and use the recirculation mode to reduce external moisture intake. Safety is crucial—foggy windows impair visibility and can easily lead to accidents, so don't take shortcuts by using cold air. I suggest placing dehumidifying pads or anti-fog sprays inside the car as supplementary measures, which are both cost-effective and reassuring. Comfortable driving in winter is key.
