AC a bit fickle / unpredictable (just me?)...

AC a bit fickle / unpredictable (just me?)...

I've had my car for a little over a month now during various kinds of summer weather weather. (Love it, but) I find myself constantly messing with the AC. I'm used to kind of setting and forgetting climate controls in my cars... maybe tweaking a little on a hot day. But in my Model S I find that I have to manually regulate the fan and keep adjusting the vents...

I notice that in most cars when you adjust the fan speed it remains relative and automatically adjusts but in the Tesla the fan speed is absolute and once set manually does not adjust.

The car is capable of cooling well, but it chooses not to at very odd times. I notice inconsistencies such as clicking between auto fan to manual and back and then having the auto suddenly jump to a new speed, as if it just sensed that it is really warmer than it registered before...

I am curious as to where the temperature sensor is and whether smarter software is in the works. It seems like there is so much opportunity for software upgrade to this ala the way the Nest thermostat works... learns your preferences. I don't know if the car has humidity and light sensors, but if it does it seems like they could do a lot.

Or maybe mine is just not working properly? :) Does anyone else notice these issues?

Mireille '&... | September 5, 2013

We live in Phoenix so the AC gets lots of use. What works for us is leaving everything on auto and adjusting the temp a bit when needed. It keeps us cool, even on the hot (120) days.

jeremythehunt | September 5, 2013

I find that leaving everything on auto doesn't necessarily provide a consistent experience as it does in my other cars. I do notice that from time to time it just randomly decides that it isn't the temp it thought it was and goes from low to very high all of a sudden. In my other cars I can pick a temp and leave it, in the S I find myself having to often adjust up and down to find a comfortable spot. I was going to take it in and have service look at it but it seems like lots of people have some sort of issues in this area so I haven't bothered.

shop | September 5, 2013

Yeah, I leave everything on auto and just bump up and down the temperature setting a degree here and there to suit what I'm feeling at the time.

Carefree | September 5, 2013

Phoenix resident - we leave everything on Auto and it works great that way. | September 5, 2013

I am also in the leave-it-on-auto-and-play-with-temp camp. Seems to work well for me in both normal and range mode, even on 100+ days.


mortgagebruce | September 5, 2013

My car is in the shop right now and the a/c is one of the things I've got them looking at.

There are times that after I enter the car on a hot day with the a/c on auto it goes to the highest setting but then it doesn't want to pull off that setting. I can be on the highway with the car totally cooled and it still wants to blast on 11. If I turn if off and then back on it will adjust or if I reboot the car it will adjust.

My a/c also has an intermittent issue with vibration through the steering wheel and accelerator and there are times when the normal loud noise from it gets abnormally loud. I actually pulled out my iPhone and recorded the sound it made one morning last week after being in the garage over night because it was in the abnormal mode. I played the sound for the Ranger so that he would be able to hear what I was trying to describe although the iPhone speaker didn't do the sound justice.

jonlivesay | September 5, 2013

Air is twitchy for me also, kind of distracts me when I'm driving. Works great most of the time, then gets crazy.

rdalcanto | September 5, 2013

I have found that if it is very hot outside, it will blow cold with the setting at 69. But if it is only 70-75 outside, then it won't blow as cold, and I have to lower the setting to 65. I'm guessing it is just trying to be efficient, but it is annoying. Just don't expect to always have it on the same setting.

AmpedRealtor | September 5, 2013

P85 w/ pano roof in Phoenix and have no trouble keeping the car cool on 110º days and while in range mode (lowered AC output). I have the temperature set to 72 and make sure I pre-condition the car about 10 minutes before I get in. It cools beautifully and to my complete satisfaction. I'm only 2 weeks into my ownership experience, so knock wood! :)

TikiMan | September 5, 2013

No problems from my prospective. I love the fact that the A/C doesn't take power from the motor (like on ICE cars) thus you can run the A/C it full-blast, and still spank the crap out of a sweaty 911 driver! :-)

ThorensP | September 5, 2013

I'm finding that my A/C is inconsistent and has a difficult time cooling the car consistently, and I live in Northern California where it doesn't get that hot.

Also, I'm finding that when I look at the Interior Temp on the iPhone App it often shows a temperature 10-15 degrees higher than it really is.

AmpedRealtor | September 5, 2013

The interior temperature sensor is located just above the two USB ports in my car, it is a round pattern of small holes in the plastic. My AC functions really well. In fact, yesterday I was downright cold while it was 108º outside. I actually had to turn up the temp to stop shivering. This was in range mode when the AC output is reduced. I keep it set to AUTO and it suits me perfectly.

If the AC cuts out or you feel it's not cooling properly, it couldn't hurt to have your service folks take a look at it.

JPPTM | September 5, 2013

AR-us early adopters do not have the perforated holes in the center console above the USB ports, so not sure how the HVAC system sensors work on our revisions.

fluxemag | September 5, 2013

I leave mine on auto, but fiddle with the temp between 66-69 (very occasionally 70). It doesn't really bother me because I have temp on the right scroll wheel. Pre-cooling is the best feature I have ever encountered on a car in Phoenix. People at work hate me about it. And since I now have a free charging station at work, I'm very liberal about pre-cooling. Yesterday I forgot to put the sun shade on the windshield, and I have the pano roof as well. After 4 hours in the afternoon sun, the app said 140! 15 minutes later, 79 :) And I thought I needed air conditioned seats...

Sanjuro88 | September 5, 2013

A/C works fine for me. Some of the problem may be due to the fact that Model S is such a voluminous car (large interior volume) and it may be difficult to cool it fast and evenly.

It has been said that tinted windows and parcel shelf helps in keeping the car cooler, in addition to "pre-cooling" the car with venting and activating A/C with your iphone app, 5-10 minutes before you getting into the car.

Anonymous | September 5, 2013

Pre-cooling only has to run 3-4 minutes to cool it down from 100. I am like most people; leave on AUTO and play with the temp level. It's not perfect, but very few cars are (even my S550 had the same problems with air). Also, I have the parcel shelf; I think that helps.

thranx | September 5, 2013

Try making sure the vents are aimed away from the temperature sensor. That way the sensor will get a better and more consistent reading on the car's actual internal temperature.

tes-s | September 5, 2013

I find the AC works very well, but often have to turn it up or down. Leaving it at a specific temperature it never seems consistent - sometimes I am hot, and sometimes cold.

In my other cars I very rarely have to adjust the temperature - they seem to do a much better job maintaining a constant temperature.

jat | September 5, 2013

I have the same experience, and my guess is they have a poor sensor location that gets hot on long trips.

earlyretirement | September 5, 2013

I notice the same type of thing. Don't get me wrong. As others mentioned it works really good the AC and keeps the car cool but I just keep it on auto and adjust the fan up or down. I find I have to do that quite a bit more than other cars that I've owned.

I do occasionally get the loud fan noise when I'm first turning my car on and it's hot out. I don't know enough about the car if this is normal but it seems abnormal to be that loud. It's a bit embarrassing sometimes when I'm driving through a drive through picking up food as it's so loud.

It seems to stop once the car is cooled but I will ask them to look at that when they pick up my car next week to fix the paint scratches I had upon pick up.

Keith72 | September 5, 2013

I live in the Houston area and have not had these issues. Mine is set on auto, and I almost never change the temperature settings.

Brian H | September 5, 2013

Range mode will prevent the loud "11" bursts. Try that.

DC@Tesla | September 5, 2013

Same problem here. I've learned to live with it. I think it has to do with the small vents, and trying to save energy. It seems to depend on the temp difference between outside and inside too (a bigger differential leads to a more active AC that keeps the noisy high fan speed for way too long).

kjin7117 | September 5, 2013

I keep temp on LO and adjust fan speed w scroll wheel as needed. Vent mode is virtually useless to me since I can barely feel it unless I blast fan speed on high.