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Windshield defroster fuel cost.

Discussion in 'Gen 2 Prius Main Forum' started by ducksoup, Jul 4, 2009.

  1. ducksoup

    ducksoup New Member

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    The windshield defroster can also be used to cool the interior of the car, although not as much as the air conditioner. Using the air conditioner reduces fuel economy, does using the defroster do the same?
     
  2. firepa63

    firepa63 Former Prius Owner

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    When the defroster is on, the AC compressor is running. Therefore, there's no savings by trying to cool your car with the defroster. Leave the climate control in Auto A/C and adjust the comfort level by adjusting the temperature. I leave mine there year round.
     
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  3. Tideland Prius

    Tideland Prius Moderator of the North
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    Selecting Defroster will keep the A/C compressor running (regardless of your previous setting or whether the A/C light is on or off).
     
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  4. richard schumacher

    richard schumacher shortbus driver

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    Using the defrost setting to cool the car would use more fuel because the cooled air would be heated by flowing past the glass.
     
  5. ducksoup

    ducksoup New Member

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    Good thinking, thanks.