# A/C Power in new cars **URL:** \ **Category:** Factual Questions\ **Created:** [January 17, 2014, 5:56am UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046 "2014-01-17T05:56:33Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [January 17, 2014, 5:56am UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/1 "2014-01-17T05:56:33Z")
Does a modern car Air/Con unit make you as cold as an old car A/C unit? People spend a lot of time thinking about the Efficiency and Power of air/con units. Cecil has written several times [http://www.straightdope.com/columns/read/2961/has-auto-ac-been-improved-so-much-it-s-no-longer-an-energy-sink](http://www.straightdope.com/columns/read/2961/has-auto-ac-been-improved-so-much-it-s-no-longer-an-energy-sink), [http://www.straightdope.com/columns/read/1010/what-gets-the-better-gas-mileage](http://www.straightdope.com/columns/read/1010/what-gets-the-better-gas-mileage) about car mileage with Air Con. in cars. But what I’m currious about is just if they are putting ‘smaller’ a/c units in modern cars. I can remember 20-30 years ago, the A/C unit blasting out cold air. Now all I get is ‘cool’ air. Of course, in those days the A/C unit had maybe 2-4 outlets, not 8-10. What do you think? Any numbers? ---
**Author:** ![randompattern](https://avatars.discourse-cdn.com/v4/letter/r/7993a0/32.png) [@randompattern](https://boards.straightdope.com/u/randompattern)\ **Post date:** [January 17, 2014, 6:17am UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/2 "2014-01-17T06:17:43Z")
I’ve noticed that since the refrigerant changed from R-12 to R-134 it doesn’t seem to get as cold. But the new stuff is better for the environment. No CFC’s ---
**Author:** ![BorgHunter](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BorgHunter](https://boards.straightdope.com/u/BorgHunter)\ **Post date:** [January 17, 2014, 2:35pm UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/3 "2014-01-17T14:35:02Z")
> [@randompattern](#): > > I’ve noticed that since the refrigerant changed from R-12 to R-134 it doesn’t seem to get as cold. But the new stuff is better for the environment. No CFC’s Some OEMs are switching to [R1234yf](https://en.wikipedia.org/wiki/2,3,3,3-Tetrafluoropropene) due to the atmospheric effects of R-134a. Unfortunately, there’s still some debate as to the flammability of R1234yf, which is (understandably) slowing adoption. ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [January 17, 2014, 8:34pm UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/4 "2014-01-17T20:34:00Z")
Today’s car AC has about 40 degrees drop between intake and output, the same as earlier AC did. Some folks would say your perception of cooler AC in olden times might be due to climate change, but I won’t go that far. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [January 18, 2014, 8:55am UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/5 "2014-01-18T08:55:45Z")
> [@AskNott](#): > > Today’s car AC has about 40 degrees drop between intake and output, the same as earlier AC did. Some folks would say your perception of cooler AC in olden times might be due to climate change, but I won’t go that far. Thanx AskNott. Is that the temperature difference ‘at the unit’, or ‘at the air vent?’ I’m wondering if my cars mix the air befoe pushing it out (which would be sensible), because no way am I seeing a 40 F difference at the vent. Anyway the oldest A/C units I can remember used to spit out drops of water too, which helped you notice how cold they were… ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [January 18, 2014, 2:47pm UTC](https://boards.straightdope.com/t/a-c-power-in-new-cars/679046/6 "2014-01-18T14:47:19Z")
I normaly insert the thermometer into the center dash vent when checking. I also check them in the shade inside a building with open doors. On the average I would say 40 degrees is pretty accurate. The cold air immediately starts to mix with the warm air in the car once leaving the vent. I will normaly weight about 5 minutes before I start taking temp readings. I don’t see many that are blowing out air below about 40 degrees on cooler days they cycle off for longer periods.