It’s summer, and if you live anywhere the sun shines, science dictates that it gets stupid hot inside your car when it’s closed up and baking in the sun. According to this Japanese video, rolling down one window and opening and closing the opposite door a handful of times will quickly and effectively cool down a hot car.




The video’s only two and a half minutes, but unless you understand Japanese (or can read the Chinese subtitles), jump straight to the 1:52 mark to get the picture. Reddit user binarysolo offers this loose translation:

Roll down a window on a side of the car. Let’s go with the driver’s side window. Go to the opposite side door (in this case, passenger side) and open/close it ~5 times. Just do this normally. SCIENCE: What we’re doing here is to help circulate air by drawing the hot air out from the opening/closing door, and causing the cool(er) air to enter the car. So... be careful. Don’t accidentally jam your hand against the door. Also, do this when nobody is next to your door so you don’t slam it into them.


In the video demonstration, the temperature outside the car was 86.9 F, and the car went from 106.8 F to 92.3 F. Your mileage may vary, but the Reddit users who tried it seem to be reporting good results.

We’ve looked at how to cool a hot car with some simple thermostat management, but, unlike this simple trick, you still have to suffer the heat of your oven-like car while you wait for the A/C to kick in. Give it a try and let us know how it worked for you (or how you quickly cool your car) in the comments.

King of living ideas - let the car drop rapidly approach the temperature (Google translated from Chinese) | YouTube via Reddit


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