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WTF, A/C compressor always on?

24K views 24 replies 8 participants last post by  Server 
#1 ·
My 2011 Sporty came with the Dual Climate control system, and I'm not used to how they work,,, But, I have found out the compressor is running almost all the time! From the 74 degree setting, and on down! I have set it on 72, 70, & 68 degrees lately, with the fan on 2, or 3, without turning on the A/C and was wondering how, & why, it kept the Sporty comfortably cool without the A/C light being on?

It's hard to tell by looking at the compressor pulley, But I hear a faint ball-bearing type noise thru the vents on occasion while it's on, and quiet in the car, and I also noticed the telltale puddle of condensation under the car on occasion?

This has got to be killing my mileage :(

Plus on longer rides it gets a bit too cool in the car, I just want fresh cool outside air when it's available, not constant A/C , but I'm not sure how to do this? Disable the CC for a fan controlled vent? because it keeps reverting back to Auto!?
 
#3 ·
I know that,,, It's not set on defrost, just the upper, or lower (body) vents, or either one.
 
#4 ·
What is your outside temperature? 70ºF and lower seems rather cool; our standard setting is about 78ºF with the outside temperature commonly about 90 to 95ºF.

I find that either domestic or auto AC will only cool to about 15ºF below the outside temperature without going to an industrial-scale compressor, so if your outside temperature is around 85ºF, it's not surprising that the compressor is running a lot. In the domestic situation, I'm happy if the compressor runs about 50% duty.

You should be able to turn off the AC and get cool outside air. A couple of our cars have non-climate-controlled AC; just a thermoststat. In cold weather, the compressor hardly runs at all, and then I open the vent to admit fresh air. I never actually turn off the AC control, just let the thermostat do its job.

It's generally said the AC gives a 2 MPG penalty, but this depends on the compressor duty. That's roughly the difference I notice between Summer and Winter.
 
#5 · (Edited)
WryCuda,
I think you missed the point. I am unable to disable Climate control (so the compressor won't run), to pull in just outside air, nor will the fan run to bring it in, as soon as I go to turn up the fan it defaults back to Auto. There is no vent setting on my Sporty?

That's the point, a setting of 74 degrees, instead of getting outside air, the heat goes on!?

There is a page in the owners manual that I'm experimenting with right now, that might accomplish this, it is Section 4 page #95.

I'm hoping it shuts off the A/C compressor, until it gets too warm and I need to just push the A/C button.
 
#8 · (Edited)
I did read the manual, did you notice my reference to it?

Again, When I turn off the Auto function, then go to turn on the fan, or change the Temp, it defaults to Auto.

By the way, I almost always have the Recirculate off/Fresh air open! But, it does me no good if I can't turn on the fan, or set the Temperature. A Catch 22 situation for sure.

By the way, I used the procedure I mentioned from the operating manual, and I believe it works manually now. It appears after a short ride to the store, that the compressor is off, ambient temp air is coming in, and I can still set the temp, & fan speed. Plus, if I need A/C I just press the A/C button now. Not sure about the compressor powered defrost, if it works the same way (by just pressing the A/C button),,, But, I will test it further. The final test confirmation would be No telltale condensation puddle under the car with the vent open, & temp set at 66 degrees. We'll see?
 
#7 ·
I have a 2013 SX and have been wondering the same thing. Do you have the cooled glove box? There is a little door inside the glove compartment to close off the air, but even closed it feels cool to the touch so I don't know if closing the door actually shuts off the AC or just stops the AC from flowing in.

Seems very inefficient if it doesn't shut it off.
 
#9 ·
It just stops the A/C from flowing in.

On my 2011 EX, Just like if you need a light for the glove box, you must turn the lights on for it to work.
 
#12 ·
For those who would like to know how to disable the compressor, & get outside ambient air through the vents, Here's more info.

Running errands, with outside temps running between 65-70 degrees, and with sun load it gets warm in the car. So, I set the CC to 68-70 degrees thinking I'm gonna get just fresh vented ambient temp air. To my surprise the air from the upper & lower vents is cooler then outside air, and after awhile it gets too cool, and I realize the A/C must be on, but no light?

Then when I shut the car off, and stop to go to the store, I notice a condensation puddle at the A/C drain spot each time confirming what I thought.

Being there is no vent switch, button, or lever, then the CC & compressor is always running, robbing horsepower, & gas mileage.

*Now, after using the procedure I mentioned previously from the owners manual, "disabling the defogging mode" the compressor, A/C, & Cold defrost don't come on until I hit the required button!
 
#19 ·
Sorry, Just realized apparently I never posted the link :rolleyes: Here it is on page #4-95 of the owners manual, under "defogging logic".
 
#13 ·
Operator error: system working as-designed. Just set the temperature where you are comfortable and leave it on AUTO. When it's cold in the car, heat will be added and the floor registers will be engaged. When it's hot in the car, dash or dash/floor registers will be engaged. When you first start up, the DEFROST function is enabled to prevent fogging. Most cars have been this way for about ten years. At ambient temps below freezing, the compressor will be disengaged for protection. The AC light does not cycle on/off with the compressor. In manual mode, you can engage the compressor and the light will stay on.
 
#14 · (Edited)
Operator error? I don't think so! Long rides like a 1-1/2hr. ride to, & from the Casino, set & holding at 68-70 degrees, with having the A/C compressor run with outside temps in that range? Alternating mid, & lower level ducts, not upper (defrost) ducts. Why can't I just get vent air!?

My 2002 Santa Fe LX was the only other car I owned with CC, and that had a way to open the vent, plus it also had an outside ambient air temp display. No CC on my last 2 Tucsons.

there is no maual mode, or I'd be able to disengage the compressor.
 
#15 ·
I have a 2011 Sportage SX with AutoClimate Control as well and had the same observation of AC working on days when it really didn't seem to be needed. The solution is found on page 4-89 - Section on Automatic Heating and air conditioning.

To Summerize it says that hitting any of the 1) mode, 2) AC 3) front defrost or 4) fan speed buttons takes the system out of auto mode for that function only.

to quote.. " the selected function will be controlled manually while other functions operate automatically".

therefore all you need to do is, (from being in auto mode), press the AC button which turns on the AC and makes the led glow green, then hit it again to turn it off. The AC will now not come on automatically...you must press the button if you want to force it on...works for me!
 
#20 ·
In my EX owners manual, this information is listed on page 4-88, But, this sentence: "the selected function will be controlled manually while other functions operate automatically" is not there?

Neither is the summary you posted!?
the wording is completely different?

Anyway, running errands today, the outside temps ranged from 60 to 70 degrees, and setting the inside temps at 68-72 degrees, I had constant A/C and the car got too cold! Plus the Compressor was running leaving a condensation puddle at each stop! All the time, the A/C light was not lit! I just want cool outside air!, :( not A/C :mad:
 
#17 ·
A/c indicator should help

Set your mode to "Auto" and set the temperature somewhere around the outside temp or more.. the indicator light on the A/C button "off" means the thermostat has switched off the compressor, if you still continue to hear the noises you said of the compressor being ON, then its worthwhile a double check... good luck.
 
#18 · (Edited)
To me this appears to be a Kia engineering flaw when it comes to 'auto climate control'. After fiddleing with it and trying every possible combination, I have concluded the only way to stop the compressor from running is to remove auto mode and disable the auto defogger especially in winter. The auto climate control does work as does the auto defogger but you loose any kind of user control of the compressor thus distroying your gas mileage and a few ponys. As far as I know, there are two compressor modes. 'Active' with AC turned on and 'Passive' with just the fan. Eitherway the compressor always runs.

The problem for most people who are accustomed to smartly regulating the compressor, is that with other manufatures the compressor normally shuts off completely when AC is not engaged. Only the sound of a quiet fan air (fresh or recirculated) is heard. You can confirm this kia anomoly by looking at the RPMs as BOTH Fan without AC compressor and with AC COMPRESSOR cause the idle to move up. I believe this was possibly implemented by design to overcone many complaints of foggy windows from excessive engine heat seeping out and incorrectly using the climate control.

This issue has been covered before and my best solution was disabling the Auto mode and auto defogging. A software update could in theory allow for compressor only when AC on, but that would not be likely unless many people complained.

Hope this made sense. Search past posts as this was covered.
 
#22 ·
The Tucson has these same HVAC issues, and I'm guessing the Sorento, & Santa Fe, have the same issues too. No wonder my gas mileage is never consistent! This, plus different brands of gas.:rolleyes:
 
#23 ·
They're not 'issues'. You're trying to defeat the purpose of a very well-engineered climate control system. Why not just relax and go with it? You'll probably like it. After getting used to mine, when I drive another car with only manual AC, I feel like I'm constantly having to fiddle with it. Makes me miss the Sportage.
 
#24 ·
IMO, it's not "well engineered" if it doesn't have a vent feature for fresh outside air?

Today I shut off the "defogging logic" as described in the manual, and this afternoon I got fresh outside air through the vents, and the A/C compressor was off!
 
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