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Best way to cool a car

What is the best way to cool a car’s interior? I had friend who would not turn on the a/c in the summer until we had driven several miles. What possible reason could he have? Everyone else always put the a/c on full blast. Is it cheaper to drive for a while? Does the condensor take time to cool?

AC on full, on recirculate. There is no reason to drive a while first. Turn it on right away.

Well driving a short while will save a little fuel, but far too little to measure. The theory works, but many people forget that most cars have more drag with the windows down, so that negates any saving.

Either way it is a lot of worry over nothing. Turn the A/C on and drive. Be comfortable and don’t worry.

Have you noticed that, while people are generally sensible, they do come up with some crazy ideas? Nutty reasons for doing silly things are all over the place.

What I have never understood is why people don’t let some of the hot air escape before jumping in, turning the Air on max with everything sealed up, while everyone cooks waiting for it to cool the super-heated air? (Btw, the air-drag/gas saving equation doesn’t matter when you first start out, unless you are at a rest stop and gettting right back on the interstate.)

So-called “common sense” is only common to those who think their idea makes sense.

In some states (the more southern states) you can put tinting on the windows to keep the interior temperatures down a bit, reducing the load on the A/C (and keeping the passengers more pleasant in the meantime).

Driving for a few miles doesn’t make any logical sense to me, but if I were him, I’d put down the windows when I first got in the vehicle, turn the A/C up, and let the wind/evaporation factor start cooling the interior much more quickly, just moving the air can lower the temperature several degrees, depending on how hot it is, and how much air you move.

You can settle your dispute with a stop watch and a thermometer. Have you tried that?

My brother in law does the same thing. It drives everyone crazy. Not only does he wait to turn on the A/C, when heading home, he turns it off several blocks away from home. I don’t get it. I think it has something to do with the compressor and how he thinks this will make it last longer.

There are several urban legends that could be true. One is that the A/C cools faster with the fan at the #2 setting because at faster fan speeds the air mooves past the cooling fins too fast to be cooled as well. Personally, in my experience in the hot southern sun, this is hogwash. I have a thermometer in my car and in hot summer highway driving, the fastest fan speed brings the temperature down the farthest.

If it’s well above ambient in the car it cools faster if you drive for a bit with the windows down to allow the air inside to get somewhere near ambient, but that’s really the only benefit. If that’s your friend’s reason, I agree with him/her.

Get one or two of those little clip on style solar powered fans that sit on your window.

I’ve always started the car, put the a/c on FULL with fresh air on, opened all windows to blow out the hot air for a few seconds, then rolled 'em up and drove with a/c on full on recirculate until the interior was cool enough, then fresh air with a/c. Rocketman

Paint your car silver or white…

Turning the AC off a few minutes before turning the blower off will help in preventing mold from growing.

Since it can get brutally hot here in OK (100-110) what I usually do is go ahead and turn the A/C on, crack the windows on both sides about 1/3 of the way, and take off. Movement of the car will draw a lot of the excessively hot air out within a few minutes and up go the windows.

Cheaper is not an issue here as any fuel savings are so negligible as to not even be noticed.

Rocketman, I think you have the right advice. But while we are at it, I know folks who turn off everything that is on before they get out of the car.

It’s almost like the question if your coffee is cooler if:

  1. You pour it hot, put some milk in it and wait for 3 minutes
  2. You pour it hot, wait for 3 minutes and HEN out the milk in it

Correct answer: 2. Because the temperature difference between the coffee without milk and the environment is greater so it cools down more initially.

Applying the same idea it appears reasonable to open the window first to vent the worst heat (and take advantage of the high temperature difference). Once the worst heat is out use the AC. But as people mentioned: The difference is so miniscule that it would be hardly measureable.

Well, right now here in Missouri, if you opened the windows for a while I’m sure it would cool down fast. The high for today was 18*.