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BLTHNDR Veteran Author Chicago Posts:462 Points:174,995 Joined:Apr 2004	Message Posted: Jul 17, 2012 9:12:09 PM Ignore BLTHNDR Report Abuse Leave your air on and drive with the windows closed, much less drag on your auto and more comfortable too. Try it and compare the results.I hope its true. [Edited by: BLTHNDR at 7/17/2012 9:12:49 PM EST]

BLTHNDR

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Chicago

Posts:462
Points:174,995
Joined:Apr 2004

Message Posted: Jul 17, 2012 9:12:09 PM

Ignore BLTHNDR Report Abuse

Leave your air on and drive with the windows closed, much less drag on your auto and more comfortable too. Try it and compare the results.I hope its true.

[Edited by: BLTHNDR at 7/17/2012 9:12:49 PM EST]

REPLIES (newest first)Ignore Short Messages

dgsteven All-Star Author Los Angeles Posts:777 Points:202,900 Joined:Oct 2012	Message Posted: Jan 3, 2013 4:10:01 AM Ignore dgsteven Report Abuse always keep comfort for myself
dieharder Rookie Author Ottawa Posts:48 Points:215,530 Joined:Sep 2011	Message Posted: Nov 7, 2012 12:09:50 PM Ignore dieharder Report Abuse Newer cars have more efficient AC systems than older vehicles. These days it is hard to find a vehicle that gets better gas mileage windows open than closed with AC on.
13Octane Champion Author Tucson Posts:2,147 Points:332,165 Joined:Aug 2005	Message Posted: Nov 5, 2012 5:27:20 PM Ignore 13Octane Report Abuse agree
sagnat Champion Author Riverside Posts:1,139 Points:304,485 Joined:Jun 2012	Message Posted: Oct 8, 2012 3:09:22 AM Ignore sagnat Report Abuse If the temp is below 80 I'll crack all the windows about 1-1.5 inches. Once it hits 80 I put on the A/C. On long drives I will leave the recerc on and shut the A/C off when climbing hills and turn it back on going down.
charladan All-Star Author Virginia Posts:564 Points:447,165 Joined:Jun 2011	Message Posted: Oct 8, 2012 1:17:56 AM Ignore charladan Report Abuse yes
buickentury Veteran Author Madison Posts:291 Points:175,995 Joined:Feb 2006	Message Posted: Jul 21, 2012 10:51:47 PM Ignore buickentury Report Abuse Windows down provided its not extremely hot. AC really seems to sap the power (and mileage) on my vehicle.
Titanic1985 Champion Author South Carolina Posts:6,218 Points:355,070 Joined:Dec 2010	Message Posted: Jul 21, 2012 3:18:31 AM Ignore Titanic1985 Report Abuse Hello DHomz. You said, "Also, you can turn the temperature up so the AC doesn't run all the time, it doesn't have to be on the coldest setting. The A/C clutch will cycle less often." This is not a true statement. The temperature setting ACtually is allowing more heated water from the engine cooling system to mix with the colder air-conditioned air. Auto air conditioning is very simplistic. First, the A/C must be turned on. It's main controls are computer or vACuum, which can turn off the A/C clutch when more engine power is required or the temperature of the engine increases beyond what a cooling system can handle. The evaporator coil in the dash has a temperature probe to prevent icing up of the coil which if allowed to freeze would block air flow from the interior fan or burst the coil itself and the A/C off switch which terminates DC power to the A/C compressor clutch. Technically, the A/C clutch is not thermostatically controlled unless you have climate control. Turning down the fan speed will cause the evaporator coil to sense less air flow, the coil will get colder faster and the AC clutch will disengage sooner & more frequently. You will experience diminished cooling in the vehicle's cabin. All of these switches & sensors are in series to control the compressor clutch. If one of these opens, the A/C clutch disengages. Corn440 has it right when he says, "I think the key is max/recirculated A/C instead of cooling and dehumidifying the great outdoors." To ease the load on an AC unit, it is best to first set your fan on high to exhaust the high interior temperature. Most vehicles have exhaust vents in the rear, usually behind the tail lights. Then put the A/C in the recirculate mode which is predominately interior air with a small mixture of outside air to prevent stale interior air. Recirculated air is not 100% interior air. Simply put auto A/C works when the compressor runs. Controlling the A/C compressor clutch regulates just how cold the temperature is, assuming you have sufficient Freon and a properly working system. Further information regarding auto A/C can be found by using Google searches as there isn't enough spACe on this forum to go into every detail. [Edited by: Titanic1985 at 7/21/2012 3:25:03 AM EST]
KansasGunman Champion Author Kansas City Posts:21,433 Points:2,104,380 Joined:Oct 2005	Message Posted: Jul 21, 2012 12:43:36 AM Ignore KansasGunman Report Abuse The only times my window comes down is to spit or shoot.
dagherrera Sophomore Author Indianapolis Posts:114 Points:69,595 Joined:Jul 2008	Message Posted: Jul 20, 2012 10:35:08 PM Ignore dagherrera Report Abuse Air conditioning when over 85-90 windows up on freeway.
DHomz All-Star Author Ontario Posts:577 Points:102,305 Joined:Nov 2005	Message Posted: Jul 20, 2012 10:45:54 AM Ignore DHomz Report Abuse If you use your A/C and drive the speed limit or slightly over (65-70mph or 110km/h), it's far more efficient than driving with windows down and doing 75-80mph or 120km/h. Also, you can turn the temperature up so the AC doesn't run all the time, it doesn't have to be on the coldest setting. The A/C clutch will cycle less often.
Jkent1953 Champion Author Salt Lake City Posts:1,976 Points:438,010 Joined:Dec 2011	Message Posted: Jul 20, 2012 10:37:15 AM Ignore Jkent1953 Report Abuse Comfort is king.
Houckster Champion Author Atlanta Posts:9,337 Points:693,275 Joined:Sep 2003	Message Posted: Jul 20, 2012 8:43:58 AM Ignore Houckster Report Abuse BLUEBERRYFOCUS: it would be interesting for you to provide a link for this. All the articles I've seen state the opposite.
BlueberryFocus All-Star Author Rochester Posts:553 Points:128,085 Joined:Feb 2012	Message Posted: Jul 19, 2012 10:20:52 PM Ignore BlueberryFocus Report Abuse I read an article recently that driving with the windows down, even on the highway is significantly more efficient than using the A/C. The test vehicle was a honda accord I believe. Mythbusters also confirmed this when they drove two identical SUVs at 55 mph with cruise control around an oval track with 5 gallons of gas in the thanks - the SUV with the windows down and A/C off drove about 15% further before running out of fuel.
BLTHNDR Veteran Author Chicago Posts:462 Points:174,995 Joined:Apr 2004	Message Posted: Jul 19, 2012 9:46:06 PM Ignore BLTHNDR Report Abuse Thats what I'm talken about Mr corn!
Corn440 Rookie Author Illinois Posts:44 Points:391,515 Joined:Sep 2011	Message Posted: Jul 19, 2012 7:49:46 PM Ignore Corn440 Report Abuse Running MAX A/C during a 2,000 mile road trip in 100-degree heat had degligible effect on gas mileage. '02 Durango 4WD 4.7L Auto got 17.2 versus EPA's 16 estimated. Needless to say I was OCD about babying the throttle the whole trip. I think the key is max/recirculated A/C instead of cooling and dehumidifying the great outdoors.
cheapmonkee Champion Author Portland Posts:30,294 Points:3,167,735 Joined:Jun 2004	Message Posted: Jul 19, 2012 4:29:32 PM Ignore cheapmonkee Report Abuse I only use it for short term periods usually only a couple minutes or less. Such as coasting down hills or as coming to a stop. Or longer when sissy passengers start crying.
PhilT08 Champion Author Buffalo Posts:2,105 Points:120,575 Joined:Oct 2008	Message Posted: Jul 19, 2012 2:56:08 PM Ignore PhilT08 Report Abuse Houckster, The point I was making is that people are often penny wise but dollar foolish.
Houckster Champion Author Atlanta Posts:9,337 Points:693,275 Joined:Sep 2003	Message Posted: Jul 19, 2012 9:59:36 AM Ignore Houckster Report Abuse REB4 writes: And if wife's in car, it's on when she says so... _____ Very wise REB4, you gotta sleep some time.
rjro Champion Author Albany Posts:1,237 Points:498,275 Joined:Jan 2011	Message Posted: Jul 19, 2012 8:24:43 AM Ignore rjro Report Abuse Depending on temp and humidity is how I determine if I use air.
Houckster Champion Author Atlanta Posts:9,337 Points:693,275 Joined:Sep 2003	Message Posted: Jul 19, 2012 8:11:18 AM Ignore Houckster Report Abuse Relative to PHILT08's comment: What's the point here? It seems to me he's trying to portray people who like to conserve fuel as somewhat silly. Save a drop of gas here but be energy wastrels elsewhere? I don't use the air much or at all around town even when the temperature is over 90. I just like saving that gas and avoiding the pollution that is caused. It's just a personal preference and even if it is hot outside there's enough of a breeze from driving to keep me sufficiently cool. I've always liked to keep fuel consumption low, even when gas was 32¢ for regular. At home I will use the A/C but I try to keep it at a high level to minimize power consumption and I bought the highest efficiency unit I could find. I use fluorescent lights and only the minimum lighting necessary. There is a great deal of satisfaction in conservation. [Edited by: Houckster at 7/19/2012 8:13:50 AM EST]
W707 Champion Author Pennsylvania Posts:1,453 Points:399,490 Joined:Sep 2008	Message Posted: Jul 19, 2012 2:21:10 AM Ignore W707 Report Abuse I''ll take the ac anyday
PhilT08 Champion Author Buffalo Posts:2,105 Points:120,575 Joined:Oct 2008	Message Posted: Jul 18, 2012 10:48:37 PM Ignore PhilT08 Report Abuse topics like this make me wonder about those who won't use A/C in their car because they might lose a fraction of a MPG. do these same people sit at home sweating because they are too cheap to spend a few bucks on electric for A/C at home ? do they turn off all lights and use candles at night ? I bet these same people dont think twice about burning considerably more gas at the drive through.
WEPSMAN Champion Author South Dakota Posts:10,508 Points:2,021,975 Joined:Mar 2005	Message Posted: Jul 18, 2012 10:11:25 PM Ignore WEPSMAN Report Abuse I will take the cost for comfort.
PatAZ Champion Author Tucson Posts:9,227 Points:122,020 Joined:May 2008	Message Posted: Jul 18, 2012 5:09:59 PM Ignore PatAZ Report Abuse I feel sorry for people who don't or can't use their air conditioning around here. [Edited by: PatAZ at 7/18/2012 5:10:56 PM EST]
Titanic1985 Champion Author South Carolina Posts:6,218 Points:355,070 Joined:Dec 2010	Message Posted: Jul 18, 2012 1:32:43 PM Ignore Titanic1985 Report Abuse Auto air-conditioning is an expensive option, even if its price is buried within the cost of the vehicle. It really does not make sense not to use it, if you have it in your vehicle and it is working properly. Other reasons for using it can be health related (e.g. intense heat & high humidity) or just to keep the system functioning properly. I have just handled several A/C issues off line on the Car Talk forum. You must use the A/C whether it be R12 or R134a to circulate the oil within the system and activate the belt driven clutch. Houckster made a valid comment when he said, "In the years to come, more and more cars will come with electric air making the choice to use air easier." The advent of the beltless air compressor is soon to be a reality as auto manufacurers continue to increase MPGs. This type of system has been used in conversion vans for years to provide A/C & heat to the rear unit. The only issue there is an extremely large battery (weight) and alternator (expense + weight). Reb4 probably gave the best reason of all when he said, "And if wife's in car, it's on when she says so..." Forget saving gas when the comfort of your passengers should be your major concern.
MsPeachi747 Sophomore Author Cleveland Posts:198 Points:10,430 Joined:Dec 2011	Message Posted: Jul 18, 2012 10:39:59 AM Ignore MsPeachi747 Report Abuse If you have rain guards on your front and rear windows, would opening the window not beyond the rain guards on the highway actually cut down on the aerodynamic drag placed upon your vehicle? This information is not included in the article. I do this on hot sultry days traveling from Cleveland to Akron. Anybody with any further information, please show me the facts!
reb4 Champion Author Chicago Posts:19,076 Points:1,818,125 Joined:Sep 2004	Message Posted: Jul 18, 2012 9:28:42 AM Ignore reb4 Report Abuse if it's 100 there is no way I'm not using a/c... in fact, it goes on when temp is over 85 on highway... And if wife's in car, it's on when she says so...
Houckster Champion Author Atlanta Posts:9,337 Points:693,275 Joined:Sep 2003	Message Posted: Jul 18, 2012 9:25:10 AM Ignore Houckster Report Abuse MERTIEMAN writes: Just how long did it take you to figure out this brilliant solution? _____ C'mon, a lot of people don't have your amount of experience so the comment might be helpful to a lot of people. If people just posted topics helpful to you we wouldn't have any.
Houckster Champion Author Atlanta Posts:9,337 Points:693,275 Joined:Sep 2003	Message Posted: Jul 18, 2012 9:09:38 AM Ignore Houckster Report Abuse Here's an article that some may find interesting: A/C and fuel economy Among the findings: 1) 40 MPH is about the speed when it's better to use the air; 2) the more aerodynamic the vehicle, the more fuel efficiency is lost; 3) the wind resistance a vehicle encounters at 70 MPH is 4X that at 35 MPH. In the years to come, more and more cars will come with electric air making the choice to use air easier. [Edited by: Houckster at 7/18/2012 9:16:40 AM EST]
MertieMan Champion Author Lexington Posts:14,768 Points:2,891,610 Joined:May 2005	Message Posted: Jul 18, 2012 9:04:30 AM Ignore MertieMan Report Abuse Just how long did it take you to figure out this brilliant solution?
bithehr Champion Author Atlanta Posts:1,834 Points:420,460 Joined:Mar 2009	Message Posted: Jul 18, 2012 8:34:27 AM Ignore bithehr Report Abuse good to know
Dennis783 Champion Author Des Moines Posts:13,574 Points:2,699,885 Joined:Sep 2005	Message Posted: Jul 18, 2012 7:43:14 AM Ignore Dennis783 Report Abuse I agree with the OilerFan
OilerFan Champion Author Tulsa Posts:14,028 Points:2,445,360 Joined:Aug 2005	Message Posted: Jul 18, 2012 7:40:56 AM Ignore OilerFan Report Abuse In 100 degree weather, I'm running the airconditioner whether it saves gasoline or not.