Should You Use Cold or Hot Air to Defog in Winter?

[RowanFitz]

In winter, both cold and hot air can effectively defog the windshield. Using cold air requires pressing the AC button to reduce the temperature difference between the inside and outside of the car, which quickly removes fog from the windshield. Hot air takes longer to clear the fog but helps prevent it from forming again. Winter fogging occurs due to significant temperature or humidity differences between the inside and outside of the car. If not cleared promptly, fog on the windshield can severely impact driving safety. Opening the windows to let cold air in can reduce the temperature difference and naturally eliminate the fog.