TL;DR
Do not pour hot water on a frozen windshield: thermal shock can crack the glass. Use a scraper, de-icer, and patience instead.
Checked 2 sources Season: Winter
 ## Why hot water is risky Do not pour hot or boiling water on a frozen windshield. The sudden temperature change can create stress cracks in the glass. Small chips or existing damage make the risk higher. Lukewarm or cold water is not a great default either. It may soften the ice briefly, then refreeze in freezing temperatures and make the ice layer worse. ## What works more safely Remove snow first with a soft brush. Then use a proper ice scraper: the toothed side roughens hard ice, the smooth side pushes it away. Use steady pressure, not force. If you need speed, use a windshield de-icer or frost spray. Let it work briefly, then wipe or scrape off the remains. From inside, use ventilation/heat toward the glass, without idling the engine unnecessarily. ## Prevent it the night before A windshield cover is the simplest fix. Put it on at night, take it off in the morning, and you skip most of the scraping. A garage, carport, or covered parking spot helps too. Important: drive only when the windshield, side windows, mirrors, and lights are clear. A small peephole is not enough. ## Rule of thumb Ice needs patience. Glass hates thermal shock. Hot water is fast only until the windshield becomes expensive.
Sources
Selected references used to verify or support this tip.
- Eiskratzen: So wird das Auto schnell eisfrei ADAC Β· other
- Eiskratzer: neun Modelle im Test TCS Β· other
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