Should You Use Cold or Hot Air to Defog the Car in Summer?
3 Answers
In summer, use cold air to defog the car. Here are some related tips: 1. Open windows for air convection: Crack open both side windows slightly to allow air circulation inside the car. When the interior temperature approaches the outside temperature, the fog will dissipate. 2. Use air conditioning for defogging: Press the A/C button (which represents air conditioning cooling), lower the temperature setting, activate the window defogging function, and set the fan speed to maximum. This rapidly cools the window glass surface through water vapor evaporation, achieving defogging. 3. Use defogging spray: The principle of defogging spray is to create an effective protective film when applied to the windshield.
That day while driving in the city, the weather was hot and stuffy, and suddenly the car windows fogged up. I quickly turned on the cold air conditioning aimed at the windshield, and the fog disappeared instantly. Using hot air in summer is definitely not an option because it makes the air hotter and more humid, worsening the fog and making it unsafe. I've driven several cars, and when the air conditioning is cooling, it dehumidifies and lowers the temperature, tackling both issues at once for quick and stable defogging. If heavy fog blocks your vision, accidents can easily happen. Nowadays, many cars have a defogging button—just press it for convenience. For prevention, don’t rush to put things back after washing the car; keeping the interior humidity low is better. In short, turning on the cold air when encountering fog in summer is a wise choice—safe and efficient. A few extra words as a reminder: don’t overlook small details while driving, and regularly maintain your air conditioning to avoid blockages and ensure smooth travel.
From years of driving experience, never use hot air to defog in summer as it worsens the problem. I use cold AC air which clears fog quickly – the principle being that cold air lowers windshield temperature and removes moisture, making fog dissipate faster. Hot air actually increases humidity, causing more water droplets to condense, which is unsafe. My advice: lower temperature, direct airflow toward windshield, activate defog mode. Safety first – heavy fog reduces driving reaction time and increases accident risks. Regularly clean AC filters to prevent odors and prolong system life. In rainy, high-humidity summers, pre-cool the cabin to prevent fogging. Fewer wet items inside means less fog sources. Practical and easy to remember.
