Should You Use Cold or Warm Air to Defog the Windshield on Rainy Days?

1 Answers
LaArthur
07/29/25 12:44pm
Using cold air is more effective. Here are the details: Reason: When the temperature outside the car is higher or lower than inside, condensation forms on the glass. You can also defog without using cold air—simply opening the windows will make it disappear. Warm air can also dry the fog, but it's not as effective as cold air. Warm air defogging: In winter, most people use the car heater. The method is similar to using cold air, but instead of blowing cold air, you direct warm air at the windshield. Blowing warm air essentially dries the moisture, eliminating concerns about fog reappearing. However, warm air defogging is slower than cold air, and the fog may initially worsen when you turn it on. You'll need to wait patiently for a few minutes for it to clear.
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