Air conditioner really kills mileage
 

I had the air conditioning fixed in the slug yesterday. About time, temp was in the mid 90's and the humidity was in the low 80% range. Up until I had the ac fixed I was running 90 mpg for 370 miles. I had to do about 80 miles for work and ran the air, by the time I got home it was 82.4 mpg for 450 miles. :( I knew that ac hurt mileage but the ac combined with my little engine made my poor car even worse as far as pulling power goes, I was driving with little to no wind and would compare it to driving into a 20mpg headwind.

Danncomm -

Poor little Insight. I fixed my A/C for carpooling and I saw my MPG plunge. I still keep A/C off for accelerating onto freeways. Need every once of power I can get.

CarloSW2

I am way too tired tonight to try to figure out the mileage hit the ac caused. Will try to figure out the difference tomorrow. Would figure somewhere in the 30mpg range to cause that kind of mileage hit in the 80 miles driven.

Last two weeks here I have seen the temp hit 106 with our typically higher humidity.

Sorry folks but no AC is no longer an option for this old man.

I do P&G the AC to try to minimize its impact, but in my Insight it was about a 10 MPG (out of 70) hit. The VX seems to take about a 5-7 hit.

It forces me to change my strategy and just hop on the interstate and not take more time for the back roads and avoid any idling.

When you are in lean burn, even in the 1.5 liter engine on the VX and 5th gear, the load of the AC and just maintaining speed at 62 MPH is about the max lean burn power of that car. The benefit is you spend less time on the road so the overall AC energy use is lower.

When I have to stop, I go max fan and Max AC temp (always on recirculate) to take advantage of otherwise wasted energy.

regards
Mech

Your IMA battery thanks you for AC though. I was just talking with the owner of hybridbatteryrepair.com this weekend and he says heat is the number one killer of packs.

So how do you do "Regenerative" AC?

The simple version is to hook a compressor up to a wheel and blow the cold air over a thermal mass.

There are probably more efficient schemes than that though.

Regenerative AC sounds like a good idea. I always think why do the auto-manuf. never bother to insulate the passenger cabin more properly, glass with lower conductivity that would allow smaller more energy efficient units in the cars. Passive cooling is an interesting idea I read about.
Vehicle cooling systems

L.E. it is appalling to think that the few cubic feet of cabin space in a passenger car which are 10's of times less than the size of 1 room require such vast amounts of Watts to keep it cool..

Someone at drive green expo asked a Ford rep in a meeting about this. He said they have no plans to insulate the cabin as far as he knows.

More like coatings to reflect infrared energy instead of letting it in to bake the interior.

Of coarse not, that would make sense wouldn't it? For my jeep, if I cut the ac on it is a 1-1.5 mpg detriment, which doesn't seem like much until you realize that it is about 4-6% of my overall. So it would seem that ac's in general draw up to 10% of your engine power. At least mine on recirculate/max and on low, while on the freeway the compressor only comes on for 2 or so seconds then stays off for almost 10.

well...both actually low conductivity and low emissivity (keep the cool air in when the AC is on and keep the heat out)

What is this ac of which you speak?

well...i know I'm talking nonsense because my car "don't have no AC" and even if it did I would probably keep it off :D
:thumbup:

95+ degrees...85%+ humidity.... no A/C I sweat all the time :p

Ron is correct that heat kills IMA batteries, and if your battery overheats, a blast of AC can bring its temperature down faster. Though AC use is from mandatory for the Insight. The battery fan comes on around 140F, and you can keep the cabin under 100F with a sun shade when parked, and lowering one window while driving. Add an assist/regen disable switch, and the battery will hardly ever heat up unless you're in hills too steep to EOC down. Add a MIMA or other custom fan controller and the fan will come on at a lower temperature.

I really can't fathom that combination of heat and humidity. I was really suffering on a 90F, 60% RH day.

By the way, Daox, did you check out the window tint on Ron's Insight? It's 30% VLT, IIRC, and he says it keeps things much cooler inside.

If that room was a greenhouse...

yes, i agree it's a greenhouse, but is it absolutely necessary to be like that ? :confused:

In Parris Island at basic training my brother saw a midnight temp and humidity of 99 each.

Best time for max AC is DFCO since its basically free. With 46 lights in 40 miles, it's inevitable that you will catch a couple of them. The VX's 5th gear is so tall you can get 10-30 seconds of DFCO-AC operation before engine speed drops down to low to maintain DFCO.

Just use the AC compressor, max fan, and recirculate, min temp and downshift as you slow to maintain DFCO RPM which in the VX is about 1200 RPM.

The threshold for me now is in the lower 90s temp wise and humidity here is rarely below 75%.

regards
Mech

I sometimes think about using evaporative cooling in a a car, if humidity is low it can be a good alternative, where I live it's only about 20%...
Has anybody tried to use a "swamp filter" somewhere in the ventilation system?
For short distances it might not be necesary to keep that filter swamp, just wet it at the start. The easiest I thougt is like a "straw filter" between two wire mesh to keep everything in place. Just place it in the intake of the ventilation, pour a bottle of water on, and let's go. For a longer effect you need to keep it humid, of course... not difficult though.
I also have seen this
http://www.classicaire.com/images/Ram_52Pk.jpg
Product Profile
but something like this will hurt aero too much...

Of course this is not valid for folks enjoying +75%

M

I need to get my AC fixed I thought that it just needed a charge I did not have enough to fully charge it I got another tank went to add more and the compressor no longer comes on. So now the question is wait till next year to fix it have it fixed now or remove the belt.

Does anyone know what kind of gain or rotating mass would be removed by bypassing the AC pulley (not engaged)?

If I get it fixed I think that I will be reducing my AC disable TPS% to ~15% stock is like 80%. That way I will eliminate the extra loss going up big hills and let me know when I am using to much throttle.

Is there a different system for some cars ?

Being in Scotland I'm more likely to die of exposure and trench foot than heat but I have AC in my car and I have used it - about 10 times in 5 years for about 10 minutes each time.

For some reason I have never felt any effect of using it - no power drag, no extra fuel consumption, nothing. It does work - if its on then the air from the vents is freezing. But it seems to have no effect other than cooling.

My older Peugeot 206 with climate control certainly felt the effect of AC, it would gain 5-10 mph when I switched to 'econ' mode.

Scary.

you're kidding , right ? How in the world could you tell if the thing is never on :p



Anyway, you have a high power TDI and the bigger the engine the less effect I would think.

Friend of mine has a Suzuki Alto 0.8/ 39hp and when it's on AC it barely moves along :turtle: I rode with him once on the highway, AC on and at 100km/h it seemed to be dying under us...

Maybe thats one advantage of the little car / big engine thing. I see no other advantage so far.

Seriously though no effect at all.

My 206 had the 2 litre HDi engine and it dragged a lot like you describe. A quick trip to my parents (250 miles each way) and it really stopped me cruising at anything over 75 as it just would not climb hills with AC on - I didn't actually know it was on because this car had climate control so it used it when it needed to.

But in the Fabia - nothing. When I first got the Fabia it was winter so I didn't use it. Then when I tried it worked and made me cold. I tried it again with Arragonis Jnr (who always likes to play with buttons) turning it off and on but all we got was cold. We tried it in traffic (idling) and again, no effect at all except we got cold again, no extra idling speed, no noise, nothing else apart from cold inside.

The AC was checked on its last service as a company was hoping to get some business from people who found theirs not working and was checking serviced cars with AC for free - and mine passed.

Strange.

Although I would like to change Helga for a hyperecodiesel (e.g. C1 or Bluemotion), every now and again (such as my 100 mph/ 40 MPG dash to England recently or her 110 mph on cruise control 500 metres behind a Bentley GT on the way home at 11 pm at night - he was my radar detector) she comes up with a reason not to.

She's a keeper I think. :p

for sure ! ! it's really a pity Skoda didn't come with a Fabia II TDI RS or maybe they will in the future ? I think that 7 speed DSG from the gasoline RS coupled with a TDI would really do wonders in terms of FE

C1...mm...more like a ladies car plus only ~90 Mph max. speed...like my old banger :D which for someone who travels a lot on the motorway would not make too much sense...

Polo Blue motion...now that's a different story...this one can probably cruise comfortably at 80-90 mph, maybe even 100 and that combined with 71MPG combined/85 highway...:eek: that I would definitely like to get my hands on..and would most probably fall in love with :turtle:

...here in southern Arizona during the summer months (105-115°F), A/C is almost manditory, but we do pay a penalty!

...my FE drops 10-11% with A/C on, from 39 MPG down to 35 MPG, on the highway; but even MORE so during in-city driving.

Yeah but the C1 Diesel has a turbo.

And a turbo is a wick.

And a wick can always be turned up - or indeed down as required.

And apart from the occasional 100 MPH + episode I average about 60 these days. :turtle:

Doesn't the Polo also have a turbo/intercooler ? I'm sure it does..Maybe you mean the 1.4 Hdi might have more potential .

This got me drooling :p

The Polo does also have a turbo / intercooller. But the C1 is lighter and if it's faster then its less of a 'layydeees' car.

Plus the C1 is available without any spannering :D

I do give you the argument of price difference... ~ 4.000 quid can buy you a lot of gas...even in the UK

Lighter yes. Faster (factory specs) no, also faster acceleration in Polo :D

Plus everybody knows the color code : Blue is for boys, Pink is for girls :D

http://static.autoblog.nl/images/wp/...0C1%20Pink.jpghttp://www.yourdz.com/wp-content/upl...ncept20084.jpg

Arrgh that C1 - I'm off to wash my eyes out with bleach....
(disclaimer - do not do this at home kids, its a joke)

I meant that a C1 is less of a girliewagon if its chipped (i.e. faster - all things are relative, I also mean 'less slow') but even then it probably won't match a blumotion for go.

But I suspect it would get better MPG, and it would also fall apart much faster as Polos are made from Kryptonite and Citroens from Playdough.

Of course when I say 'made' and Citroens I actually mean that some parts are randomly moved closer together somwhere in Poland and eventually called a car. If it stays in one piece then Peugeot claim it as one of theirs, otherwise they let Citroen sell it.

I have a confession, I'm even considering a Nemo Multispace / Bipper TeePee / Qubo Multijet instead - mainly so I can get bikes in.

But those go 0-60 in more time than your Corsa. In fact I think I will need a sundial, or in the case of the PSA ones a calendar. :D

Off topic Cyprus is on my list of places to go sometime soon - which part are you in ?

PS I found where your C1 pic comes from.

Hello girls.... :turtle:

From Monty Python's Meaning of Life:

Civic CX is about 4mpg

On my Matrix it drops MPG by about 5 during steady state 55MPH driving.

...we used one of those on our 1955 Ford Station Wagon in Yuma, AZ, circa 1956-59.

...worked "great" as long as you were moving.

So I have an apartment, and since the beginning of summer my internet kind of turned to crap. dropping randomly or just going really slow(like a ping time of 1000ms to Google using basic ping). Called Time Warner Cable (unfortunately my cable provider) a lot. they came at least 10 times since about may. Exchanging and replacing switches/cables/modem, EVERYTHING), still wasn't working. But over the weekend my roommate went out of town and I turned off the air cause his dumb *** likes to keep the thermostat down to about 70. And when I turned it off the internet was fine, no dropping, as soon as the air came on again, I dropped. And I guess the whole apartment complex started complaining to Time Warner Cable about it. So HOW is it that the air conditioner can affect my cable internet and how the hell can I fix it, cause time warner and the apartment complex have no idea.

^^^ Sorry, but I missed how this effects your milage :confused:

I missed that part as well. Do I report or not.... not yet but my eyes are watching

Freeway at 65 MPH -24.5
Freeway at 65 MPH with aircon -23.2

Not sticking to the steering wheel and the rest of my black interior in the heat of summer - priceless

Before I hit the submit button, I just realized that priceless actually equals .148 gallons of fuel per hour, which at $3.00/gallon, is roughly 44 cents per hour. While not free, it beats feeling all slimy from driving in the heat without aircon. :D