I know that using the AC makes your gas mileage go down. But some days you just gotta have it, you know? I'm wondering if the rate at which it effects the gas mileage is the same regardless of how cold you run it or how high your fans are turned. Or does the effect go up depending on how cold your thermostat is set. Anybody know?
2007-07-03 15:22:07 · 9 answers · asked by momto8kiddos 3 in Cars & Transportation ➔ Maintenance & Repairs
Your gas mileage can be affected by the level your thermostat is set at when the AC is on. It depends on what kind of car you have.
The most significant predictor of increased fuel use with the AC on is wether or not your AC compressor is running. Normally a large belt turns the AC compressor pulley. When the AC is working a clutch on this pulley is activated and causes the compressor to pump refrigerant through the AC system.
Some cars such as a Honda Insight turn the AC compressor off when the car is accelerating and back on when it is not.
So in this situation there is very little effect on gas mileage no matter what you do with the AC settings.
In my 91 Honda accord having the fan off turns the AC compressor off no matter what the thermostat setting is.
To save a little gas I can turn off the AC when I accelerate
by turning off the fan and then turn the fan back on again when I am driving a steady speed. Wether my thermostat is on high or low makes very little difference in my car so I get the maximum efficiency by having the thermostat set at maximum cold and turn the AC off and on by using the fan control.
If having your thermostat set to a comfortable position will allow the AC compressor to stop pumping at times then you save gas. If your AC compressor is pumping no matter what position your thermostat is in then you do not save a significant amount of fuel by having the AC at a setting other than maximum cool.
2007-07-03 16:06:52 · answer #1 · answered by Brian R 3 · 0⤊ 0⤋
Having the fan on is a minor power draw which if there is an MPG drop it would be minuscule. The AC on the other hand puts extra resistance on the motor when it's turned on which will affect your gas mileage a bit. I've done some research on this and it looks like it takes the average car one extra gallon per 100 miles driven to power the AC unit. So if you have a car getting 20MPG it would take 5 gallons to go 100 miles without the AC and 6 gallons with the AC on. And I read the other post about AC being better than having the window down and that's only partly true. If you've seen the Mythbusters tv show, they proved that windows down under 55mph yields better MPG, while with speeds over 55mph AC on is more efficient. The increase in drag at higher speeds becomes more detrimental than the power the AC compressor robs from the engine.
2016-05-17 21:48:42 · answer #2 · answered by ? 3 · 0⤊ 0⤋
The colder you want it the longer the compressor is engaged and compressing freon to cool the interior of the car.
If you use the setting that recirculates the same air in the cabin (interior) it will cool off faster and stay cooler with less contribution from the compressor. When you set it to absolute zero in the car the compressor will run indefinitely or until you turn off the motor.
Good Luck!
2007-07-03 15:33:58 · answer #3 · answered by CactiJoe 7 · 0⤊ 0⤋
From Phoenix
NO.
Yes you use a little more gas when the A/C is on, but be comforable and don't be afraid to crank up the A/C when needed.
One trick I use out here is to be moderate when the sun is behind me and turn it up when driving into the sun.
Might give you some piece of mind.
2007-07-03 15:40:22 · answer #4 · answered by Judd 5 · 0⤊ 0⤋
A higher setting does make the compressor cycle more often, so I guess it would make a difference in the mileage, sure.
2007-07-03 15:27:50 · answer #5 · answered by Anonymous · 0⤊ 0⤋
It makes very little difference because the compressor is running anytime the a/c is on. It may just cycle more if the temp is higher or the fans speed is lower.
2007-07-03 15:28:12 · answer #6 · answered by Ron B 6 · 0⤊ 1⤋
No becouse the compressor spins all the time unlike a home unit which will cycle on and off.
The mixing valve your reffering to just mixes the hot and cold airs to your liking.
2007-07-03 15:26:13 · answer #7 · answered by Anonymous · 0⤊ 1⤋
makes no difference. as long as the a/c is on you have a drag on the engine since the compressor is running.
2007-07-03 15:31:34 · answer #8 · answered by richard b 6 · 0⤊ 0⤋
if you have the fan runing no mpg it is the same
if the ac its on mpg goes down
2007-07-03 15:59:59 · answer #9 · answered by Anonymous · 0⤊ 0⤋