Q: Defroster use AC for defog?

asked by on January 23, 2017

Does the front defroster in a car use the air conditioning to defog the windows?

Hello - yes, the defrost function uses the air conditioning system to remove moisture from the air. The air is then re-heated using the heater functionality, and you now have hot, dry air to defrost the inside of the windshield more efficiently.

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