Using AC is worse then Winter Driving

[Howie411]

Well its been about 90 in Northern VA the last few days and I've been using the AC (keeping it on 68) and my MPG has dropped from 41-44 to about 30-31. This is worst then when it was winter. I guess the only time to get optimal mileage is to live where its fall all year long.

Edited April 7, 2010 by Howie411

[lolder]

At start with a warm car turn off the AC and open all the windows and (sunroof) for a few minutes. After most of that heat is gone, close up, turn the AC on to 72 or higher. It should only cost you a couple mpg. then. Watch the accessory load in "Empower". Driving with the car open for a few minutes cools quicker anyway. Park in the shade.

[Oman]

68? The amount of energy the A/C uses is exponential to the temperature differential being requested. I run the A/C most of the summer and suffer a loss of about 2-3 MPG. I keep it at about 75. Remember that there is no real insulation on the car since much of the surface area is single pane glass. Also use the recirculate option once the car cools off a bit. At 68 I bet the fan stayed on high and the compressor ran full time.

 

Jon

 

 

Well its been about 90 in Northern VA the last few days and I've been using the AC (keeping it on 68) and my MPG has dropped from 41-44 to about 30-31. This is worst then when it was winter. I guess the only time to get optimal mileage is to live where its fall all year long.

[Ranger_Rick]

A little 4.5 mile drive for me.

To: temp 63, mpg 41

Fro: temp 85, mpg 48 (fro is down the little incline)

Nice to have good mileage Spring Forth :hysterical: (windows open, climate control off)

[FFHdriver]

A little 4.5 mile drive for me.

To: temp 63, mpg 41

Fro: temp 85, mpg 48 (fro is down the little incline)

Nice to have good mileage Spring Forth :hysterical: (windows open, climate control off)

I keep mine on 72 degrees year round and the AC is on when the car is running any month of the year. The only difference I can tell is when the ICE runs more during cold weather. I get about 34-35 MPG around town in cold weather and 37-39 in hot weather.

[seminole90]

I keep mine on 72 degrees year round and the AC is on when the car is running any month of the year. The only difference I can tell is when the ICE runs more during cold weather. I get about 34-35 MPG around town in cold weather and 37-39 in hot weather.

 

This is one of my big concerns. I live in South Florida and I know I will be using lots of A/C . Today was the first time this year I needed to use my air and I noticed about 3 mpg difference but it still averaged 45 mpg.

[rfruth]

I use my A/C lots but at 78 not 68 F with blower speed somewhat high (the dehumidified air does the trick) - been lots of good tips here, park in the shade if possible, use recirc mode, let the heat vent at first, tinted windows ((not done this myself but I use a windshield sun screen when parked)) anyway only a few MPG hit :)

[lolder]

The mileage of the FFH also increases 0.2 mpg per degree F. increase; 40 degree increase, 8 mpg increase. It more than makes up for AC use.

[VonoreTn]

Well its been about 90 in Northern VA the last few days and I've been using the AC (keeping it on 68) and my MPG has dropped from 41-44 to about 30-31. This is worst then when it was winter. I guess the only time to get optimal mileage is to live where its fall all year long.

 

I worked in the Air Conditioning engineering at Ford for several years (years ago) and we ran a lot of windtunnel tests to measure speed of cool down with a 110F ambient and 130F interior starting point. Opening the windows first is a good idea, as the interior can get up to as high as 140F in southern states with the windows closed in a parking lot. Leaving a small gap at the top of the windows while parked can knock 20F off that peak.

 

Whether you start on fresh air and switch to recirculation mode makes very little difference in cool down rate, but recirculation mode is always much more efficient than fresh air mode. In fresh air mode you can spend as much as half of your AC cooling energy on extracting moisture out of the incoming air, and dumping it out a drain below the evaporator onto the road. But in recirculation mode, once you have dehumidified the air, you save that energy and just cool the same dehumidified air over and over. So be sure to push that little button on the bottom right with the recirculation symbol. If you need to freshen the air for whatever reason, just take it out of recirc for a minute or two, or open a window or the sun roof briefly.

 

Also if it's 90F outside, you don't need to put it on 68 to get to a comfortable 72, put it on 72. A setting of 68 is just begging the system to run at max capacity and energy level constantly.

 

My personal FFH experience with running the AC has been that it has been totally comfortable and it hardly has any impact on my mileage 40-42 mpg, whereas I took a big hit during cold temperatures this last winter 34-38 mpg. Thus I am impressed with the FFH air conditioning engineering, I think Ford did an outstanding job on designing it.

[lolder]

A nagging worry about our suggestions to open the windows and sunroof frequently for cool downs is the wear and tear on those mechanisms. I had a '95 Grand Marquis whose windows failed a lot. I think I coughed up about $150 about half a dozen times in 12 years. That's A LOT of gas! I wonder if these actuators are any better? Maybe they last longer if you use them more often. Anybody care to do an analysis?

[FFHdriver]

A nagging worry about our suggestions to open the windows and sunroof frequently for cool downs is the wear and tear on those mechanisms. I had a '95 Grand Marquis whose windows failed a lot. I think I coughed up about $150 about half a dozen times in 12 years. That's A LOT of gas! I wonder if these actuators are any better? Maybe they last longer if you use them more often. Anybody care to do an analysis?

I had a '96 Olds that I had to replace both rear window motors on because, the mechanic said, I didn't use them.

[Juris]

A nagging worry about our suggestions to open the windows and sunroof frequently for cool downs is the wear and tear on those mechanisms. I had a '95 Grand Marquis whose windows failed a lot. I think I coughed up about $150 about half a dozen times in 12 years. That's A LOT of gas! I wonder if these actuators are any better? Maybe they last longer if you use them more often. Anybody care to do an analysis?

 

I've owned cars with power windows for 40 years and never had a problem with them: VWs, Chevys, Fords. I hardly think this is a major reason not to lower the windows for a few seconds to cool off the car. The advice given above about sensible use of the AC is golden. Winter weather is a far far greater detriment to MPG's than sensible use of the AC.

[acdii]

A nagging worry about our suggestions to open the windows and sunroof frequently for cool downs is the wear and tear on those mechanisms. I had a '95 Grand Marquis whose windows failed a lot. I think I coughed up about $150 about half a dozen times in 12 years. That's A LOT of gas! I wonder if these actuators are any better? Maybe they last longer if you use them more often. Anybody care to do an analysis?

 

Bad year for the window regulators, the cables popped off the drums too easily. We have a 95, same thing, all 4 were replaced, yet the windows rarely were opened.

[lolder]

Bad year for the window regulators, the cables popped off the drums too easily. We have a 95, same thing, all 4 were replaced, yet the windows rarely were opened.

Same with mine. It was the cables or occasionally a stuck window, not the motors unless the stuck windows were motor brush problems.

[spacenomyous]

Hey the sales person from the dealership said that the AC had a separate electric motor to run the AC so the ICE doesn't have to run when the AC is on. Is that true, if so does it impact MPG?

[lolder]

The ICE doesn't have to run. Yes, it affects mileage. All the energy including electric comes from gasoline.

[The Chad]

Saw a great hint a few months ago (it won't help in 90 degree temperatures, but when it is slightly warmer and you want a breeze). Vent the sunroof, and ever so slightly vent the rear passenger window. This will create an excellent breeze in the car that'll cool you off, and not suffer any MPG issues (as far as I can tell).

[jay2000]

How does the FFH air conditioner control the cooling?

 

Does it just cycle on and off as cooling is "demanded"? (Like my older cars did.)

 

Or, does it run the A/C full blast all the time, and then add warm air from the heater to achieve the desired temperature? ( Like I think many other cars now do.)

 

Jerry

[Oman]

A variable speed fan controls the amount of cooling based on the difference between the set temperature and the measured temperature. The electric compressor turns on and off to maintain a set evaporator temperature (that cools whatever air is flowing through). It will also mix in hot air if needed (defrost with A/C on).

 

Jon

 

 

 

 

 

 

How does the FFH air conditioner control the cooling?

 

Does it just cycle on and off as cooling is "demanded"? (Like my older cars did.)

 

Or, does it run the A/C full blast all the time, and then add warm air from the heater to achieve the desired temperature? ( Like I think many other cars now do.)

 

Jerry

[lolder]

A variable speed fan controls the amount of cooling based on the difference between the set temperature and the measured temperature. The electric compressor turns on and off to maintain a set evaporator temperature (that cools whatever air is flowing through). It will also mix in hot air if needed (defrost with A/C on).

 

Jon

Are you sure the compressor cycles? I can't see it doing that on the accessory load meter. I thought it was a variable speed high voltage AC motor.

[FFHdriver]

Are you sure the compressor cycles? I can't see it doing that on the accessory load meter. I thought it was a variable speed high voltage AC motor.

Okay bbf2530 we await your expert knowledge on a cycling or non-cycling AC compressor. We're all too lazy to go check our cars. lol TIA

[tonifan]

I've found that, instead of having the AC on "Auto", I keep set the fan at just two notches up from "off" and the "Auto" goes off. I keep the AC at an even 68 all year, and I'm still getting long-range 40.2 MPG. If I turn on the "Auto" feature in the AC, the mileage goes down to about 37 MPG, overall. That may have something to do with it. I know that if I have the AC on the "Auto" setting, the fan automatically goes way up to about 5 notches, and doesn't ever seem to go down again much. I live in San Francisco, and keep the AC at that setting year round. Our year round median temperature is 57 degrees in S.F., but the temperature can go up to 88-98 degrees in other parts of the San Francisco Bay Area. In the cooler months here, it can go down to 43-47 degrees, and the heater comes on to bring the temperature to up 68-69. I have the AC with the two individual controls, one for the driver and one for the passenger. Hope this info helps.

[lolder]

It's not the blower fan that draws the most power, it's the AC compressor whose load can be seen in the accessory gauge in "Empower" mode. In SF you could probably leave the climate control "Off" most of the time and ventilate with the windows. For heating, that won't come on until the ICE warms up anyway. Leave it off until the ICE warms up from driving and then turn it on. It'll only be a few more minutes. There are other helpful tips also like getting you're "significant other" to get out and give you a push.

[DodgerFan]

This probably belongs in a "things I would like to see in new models" thread, but since we are talking about cooling, I sure wish Ford would have put an "auto windows down" feature in their remote. My 2003 Accord had this and I used it all the time in warmer months. I could hold down the unlock button and all the windows would go down. I could do this as I approached the car, and have it cooled down by the time I got in. It's probably the one biggest feature I miss the most. Other than that, I love my FFH!

[resq1diver]

hmm, Well, i have my ac on auto and set to 71, and get about what you are getting, tonifan...but i noticed on cooler, less humid days, like today, i was getting 43...

The outside weather does play a big role in it..

 

As long as i'm getting 40+ in the DC area, i'll keep my ac where it is and keep doing what i'm doing, since after all, 44 mile commute, i'm not going to go without ac during the summer