What A/C to use?

[gabriel9766]

So my Malibu has 2 A/C settings. It has a eco A/C and a regular/Comfort A/C. 95% of the time i run it on the eco A/C which shuts the car off more when to come to a stop (auto stop). Eco A/c is a light AC setting where its less power to drain on the engine for fuel economy. My real Q im trying to ask is should i use fresh air or Recirculation mode with the A/C to save fuel. Im a cheap [censored]. But the car does stay more cool in Recirculation mode.

 

[E150GT]

Originally Posted By: gabriel9766
So my Malibu has 2 A/C settings. It has a eco A/C and a regular/Comfort A/C. 95% of the time i run it on the eco A/C which shuts the car off more when to come to a stop (auto stop). Eco A/c is a light AC setting where its less power to drain on the engine for fuel economy. My real Q im trying to ask is should i use fresh air or Recirculation mode with the A/C to save fuel. Im a cheap [cenwored]. But the car does stay more cool in Recirculation mode.

If you want to be real cheap use the windows. But recirculation mode is where my car spends most of its time. I set it to automatic and forget it.

 

[Eddie]

I would run Rec when local driving and eco for longer highway drives. I use REC because it keeps the outside smells outside, especially diesel and oil burners. Ed

 

[E150GT]

Originally Posted By: Eddie
I would run Rec when local driving and eco for longer highway drives. I use REC because it keeps the outside smells outside, especially diesel and oil burners. Ed

yeah. If my car is not in recirc , I can smell a cigarette from the car in from of me if that person is smoking.

 

[Leo99]

Originally Posted By: E150GT
Originally Posted By: gabriel9766
So my Malibu has 2 A/C settings. It has a eco A/C and a regular/Comfort A/C. 95% of the time i run it on the eco A/C which shuts the car off more when to come to a stop (auto stop). Eco A/c is a light AC setting where its less power to drain on the engine for fuel economy. My real Q im trying to ask is should i use fresh air or Recirculation mode with the A/C to save fuel. Im a cheap [cenwored]. But the car does stay more cool in Recirculation mode.

If you want to be real cheap use the windows. But recirculation mode is where my car spends most of its time. I set it to automatic and forget it.


Does the wind resistance with the windows open take a smaller hit on the mpg than the A/c? I remember discussing this topic 40 years ago. I assume it's been resovled since then.

 

[gabriel9766]

Originally Posted By: Eddie
I would run Rec when local driving and eco for longer highway drives. I use REC because it keeps the outside smells outside, especially diesel and oil burners. Ed
i normally don't drive city unless i get off in rush hour and take the back road.

 

[danster]

The AC will always be more efficient (colder air) in recirculation mode. This is because it takes a bit of heat from the cabin air that is already cooled rather than a lot of heat from the outside air. Fresh air mode will make the compressor cycle much more. You only need the fresh air mode if you are fogging windows with the moisture from your breath.

I can't imagine there is much if any MPG difference with the ECO mode. I think it is there to make you feel good.

Please do some carefully measured MPG tankfuls and let us know

 

[mclasser]

In the summer I'm always on recirc; fall & winter is fresh air so the windows don't fog up. A/C definitely blows colder on recirc.

 

[Killer223]

what i've found living in AZ,
When you first get in, crack the back windows a little 1/2"-2" put AC on high fresh air, after moving for a min or so and the cold air pushes out the hotter air out, then switch to recirc. This has proven to be the best method of cooling off a cabin, i've tested this on every vehicle i've owned.
If you have a mechanical engine mounted fan, you can keep a lower gear for the higher RPM's and it'll cool off faster then normal driving as well. this makes no difference on electric fan equipped vehicles.

once the cabin is cool on recirc you can often turn the fan speed down and cause less use of the AC system as it's cooling already cooled air.

 

[bioburner]

Originally Posted By: Killer223
what i've found living in AZ,
When you first get in, crack the back windows a little 1/2"-2" put AC on high fresh air, after moving for a min or so and the cold air pushes out the hotter air out, then switch to recirc. This has proven to be the best method of cooling off a cabin, i've tested this on every vehicle i've owned.
If you have a mechanical engine mounted fan, you can keep a lower gear for the higher RPM's and it'll cool off faster then normal driving as well. this makes no difference on electric fan equipped vehicles.

once the cabin is cool on recirc you can often turn the fan speed down and cause less use of the AC system as it's cooling already cooled air.

Works for me. More use of the AC now that I migrate to south Tx for the winter

 

[skyactiv]

Recirc lowers the humidity more which feels better on a hot, humid day typical during a Missouri summer. Turning the AC off and driving with the windows down in city traffic saves fuel over running the AC, but not so at high interstate speeds. Todays vehicles don't have the ventilation cars did decades ago where you wouldn't melt driving in Tuscon during the summer.

 

[Mackelroy]

Recirculation mode blocks fresh air , if eco mode is cold enough run that , if not run recirc mode.

 

[HerrStig]

If you are going to run recirc all the time make sure your exhaust system is in good shape.

 

[gregk24]

I just leave it on auto and let the car do the work. Either way I don't think it will make much of a difference.

 

[gabriel9766]

Originally Posted By: gregk24
I just leave it on auto and let the car do the work. Either way I don't think it will make much of a difference.
i wish i had auto climate control. It only comes on 2LT and up models, mine is only a 1LT.