How's your AC?

[SeminoleFSU]

Part of the problem in older cars which IIRC has been mentioned before is the placement of the interior temp sensor.. Either way the system can cool the car just fine especially if you have tinted windows.. Pano adds to the load of course. Overall the auto temp will need to be a good bit lower than most cars to get the same level of comfort. This could be a pano thing, a sensor thing, or the unit is a little undersized compared with other cars with this same interior volume... Or some combination of all if these. Either way, just treat the temp as an arbitrary number and lower it more if you want it colder like others have said. Disabling range mode, recirculate, and manually increasing fan speed all help too

 

[mgboyes]

Compared to all my previous cars (Audi / Mercedes) the climate control is poor, because of what I perceive as a lack of control. I think the system is powerful enough; it just doesn't do what you ask of it.

I did 50,000 miles in my last car (Audi A8) and in 4 years I never once changed the temperature setting from the value I chose the day I collected it. It just worked. With my Model S I have to adjust the temperature every time I use the car, often multiple times per journey, over a wide range of values.

An easy way to see this is by using the remote heating feature. If on a coldish day you turn on remote heating and set a temperature say 5 degrees higher than ambient then the car will heat the cabin as you'd expect. But if you keep doing this (i.e. every 30 minutes when the remote AC turns off you immediately turn it straight back on again with the same settings) then the car will just get hotter and hotter and hotter, until it's way above its target temperature.

On the other hand on a warm day the remote cooling feature is far too weak, and never reaches its target in my experience. In April my car was parked in a sunny car park in the UK (ambient temp maybe 20C but a decent amount of solar gain). I turned on remote AC, set 20 degree C target, and watched what happened. Initially the interior reading was 29. After 30 minutes when the AC turned itself off it was 25. I restarted the AC and waited a further 30 minutes - 23. Repeated and waited a further 30 minutes - 22. So after 90 minutes the car still hadn't actually got within 2 degrees of the setpoint. I suspect I could have kept running the climate control forever and it wouldn't have ever managed to reach the target setpoint.

I'm kind of surprised they even let them out of the factory like this - as far as QA tests go "in moderate weather conditions the AC can achieve and maintain any chosen cabin temperature within 30 minutes" seems like a pretty basic one to me.

 

[ahimberg]

Comparing my old telsa (vin 37xx) to the new one (85xxx), the AC runs much weaker, I don't know how much of that is it being a different system, different tuning for newer cars to use less power, or the temp sensor location thing changing. Looking at what temps the car thinks it is at - via the mobile app, i can see it saying its 79 degrees inside the car, i have it set to 67, and the fan speed is not on very high. my memory in the old car is it would be running at full blast with that temp difference.

 

[mgboyes]

Compared to all my previous cars (Audi / Mercedes) the climate control is poor, because of what I perceive as a lack of control. I think the system is powerful enough; it just doesn't do what you ask of it.

I did 50,000 miles in my last car (Audi A8) and in 4 years I never once changed the temperature setting from the value I chose the day I collected it. It just worked. With my Model S I have to adjust the temperature every time I use the car, often multiple times per journey, over a wide range of values.

An easy way to see this is by using the remote heating feature. If on a coldish day you turn on remote heating and set a temperature say 5 degrees higher than ambient then the car will heat the cabin as you'd expect. But if you keep doing this (i.e. every 30 minutes when the remote AC turns off you immediately turn it straight back on again with the same settings) then the car will just get hotter and hotter and hotter, until it's way above its target temperature.

On the other hand on a warm day the remote cooling feature is far too weak, and never reaches its target in my experience. In April my car was parked in a sunny car park in the UK (ambient temp maybe 20C but a decent amount of solar gain). I turned on remote AC, set 20 degree C target, and watched what happened. Initially the interior reading was 29. After 30 minutes when the AC turned itself off it was 25. I restarted the AC and waited a further 30 minutes - 23. Repeated and waited a further 30 minutes - 22. So after 90 minutes the car still hadn't actually got within 2 degrees of the setpoint. I suspect I could have kept running the climate control forever and it wouldn't have ever managed to reach the target setpoint.

I'm kind of surprised they even let them out of the factory like this - as far as QA tests go "in moderate weather conditions the AC can achieve and maintain any chosen cabin temperature within 30 minutes" seems like a pretty basic one to me.

OK so I was inspired to run a simple test on this (apologies in advance that all my temps are in degrees C not F

The car is sitting in the carport outside where it's been since yesterday. It's plugged in but charging finished 12 hours ago.
Time at start is 17:00 in the UK.
Outdoor temperature (according to the car) is 15.5C, interior 18C (higher than exterior because of earlier solar gain and higher temps).
Using the Remote S* app, enabled remote heating and set target temperature to 25C (which is pretty warm, but I wanted to make the car have a decent amount of work to do).
Then every 5 minutes I took a screenshot of the app to record temperatures.
And every 30 minutes when the AC turned off I immediately re-enabled it (with the same 25C setpoint).
Car was plugged in throughout so was drawing shore power to run the heating.

* Reason for using the "Remote S" app rather than the official TM one is that Remote shows you the exterior and interior temps from the car with 0.5 degree resolution, plus the interior fan speed, and it doesn't disconnect if you leave it running for a long period.

Here's the result:

I got distracted towards the end and forgot about taking 5 minute screenshots - but the final one was ridiculous.

I really can't fathom how anyone thinks this is an acceptable behaviour from a climate control system.

This obviously isn't a compressor or cooling issue at all - the car is just heating the cabin - but it's clear that there are some pretty obvious bugs in the control logic here. It's even more strange when you remember that on 2 occasions during that test the AC turned itself off and I had to turn it back on again. So twice the system came on, discovered it had a setpoint of 25 and an ambient of either 26 or 28 and yet decided that it needed to keep heating the cabin!

 

[NOLA_Mike]

Comparing my old telsa (vin 37xx) to the new one (85xxx), the AC runs much weaker, I don't know how much of that is it being a different system, different tuning for newer cars to use less power, or the temp sensor location thing changing. Looking at what temps the car thinks it is at - via the mobile app, i can see it saying its 79 degrees inside the car, i have it set to 67, and the fan speed is not on very high. my memory in the old car is it would be running at full blast with that temp difference.

Agree with this totally. It's not that the newer car A/C doesn't work as well (for example if I move the temp to LO it will blast cold air just like the old car) but the new car is not near as aggressive at achieving the set temperature and I will often have to move it to LO when I get in a hot car.

I liked the operation on the old car much better than the new car.

 

[GaryREM]

Love my car, but, I personally find the AC to be one of the eh factors in my car. Tiny little vents that I think have gerbils behind them breathing on me. Very little air and what air does get to me seems to vary in temp. Should be fun on those super hot CA days this summer.

No body ever mentions the fact that the air vents will turn off when angled to the sides. I know that mine had been moved to the side and significantly cut down the air flow through the vents. Getting them back to the center significantly increased the total flow of air.

 

[Khatsalano]

I also find that the A/C is a little on the weak side, manual or auto control. The auto control is just as mediocre as every other car with auto climate control. We just tend to notice it more because everything else in the car is engineered so precisely, the climate control system is an anomaly in comparison.

- K

 

[zwede]

Interesting. Seems like newer cars are not as good as the older ones. Mine: P85+ VIN 15K built July '13. My AC is ice cold and will blow too much at the regular setting. I've switched it over to range mode to calm it down. I keep the temp setting on full auto, 23.5C, 74F and it cools off very quickly even in range mode and stays comfortable. I'm in TX so we have plenty of 100F days.

 

[mgboyes]

One other question that someone else raised yesterday and which slightly blew my mind:

If the cabin temperature sensor is in the center console area near to the USB ports, how on earth does the car allow the driver and passenger to have different temperatures? Surely there must be multiple temperature sensors?

 

[dieselol]

I also find the climate control system to be (what I feel is) overly inconsistent WRT comfort level at a specific temperature and I find myself having to adjust the temperature setting quite often.
Disappointing for a vehicle that seems to advertise using tech to make it easier on the driver. (Same goes for the audio player)

 

[tcampos]

I have a P85D (December manufacture) and this is my second Model-S. Compared to my first, the P85D has seemed to me to have MUCH worse AC performance. So much so, I complained about this when I took the car in to get my Ricaro seats installed. I was able to show to Tesla that there were times where the car said the internal temperature was 85 degrees, the thermostat was set to 70, yet fan speed, etc did not reflect the fact that the car was so warm. During my service, they gave me a P85 loaner which clearly demonstrated the contrast. After showing this to Tesla, I got the following response:

Your older car had a much different HVAC system with sensors located in different areas of the cabin. The newer generation HVAC system uses outside ambient air temp, outside sun/heat load and inside ambient air temp to calculate the logic for the HVAC system. We were able to replicate your concern or what we thought was close to it when we had your car and another car parked outside. [...] We asked the Service Engineer about this and he said it was normal. We expressed out concern that they both felt the same but the cars reacted a little differently. He is aware of this issue and he said it was a part of a new HVAC software update scheduled to be released soon. He confirmed that the inside ambient air temp is not heavily weighted in determining the HVAC actions but could be.

All of this to say, it is normal and I know you might not like to hear that right now but we have been very thorough in testing [...]

I appreciated the fact that service took my concern seriously and did a pretty thorough test to confirm the behavior of the car. I've accepted the fact that the car is performing as they've designed it, but I think it is terrible cooling performance for a luxury car. I know Tesla reads these forums, so I strongly encourage anyone who feels as I do that the AC performance on the newer cars is suboptimal to state your experience.

 

[FlasherZ]

I just completed an Orlando to St. Louis drive with my family in the car (and 2 kids in the third-row seats). In the 102-degree Florida heat for several hours of driving, I found that setting my Signature's temp at 67 degrees with the fresh-air setting turned on was the most comfortable for everyone in the car.

My car has 3M tinting film all the way around, except the windshield (it's illegal in Illinois) and pano roof.

 

[Max*]

My AC on a 2015 is very weak... I thought it's just me, but nope.

 

[mknox]

In the 102-degree Florida heat for several hours of driving, I found that setting my Signature's temp at 67 degrees with the fresh-air setting turned on was the most comfortable for everyone in the car.

That's exactly where I keep mine and I too find it is more than adequate. Southern Ontario can get very hot and humid in the summer. Haven't hit a 100 degree day yet this year, but we do get 'em. Mine is an early 2013 car, so that may have some bearing.

EDIT: No after market tint at all on my car.

 

[beeeerock]

Interesting that I came across this thread today, after speaking to my service adviser yesterday afternoon!

Compared to my previous '09 Mercedes with dual zone climate control, the MS HVAC system can only be described as 'poor'.

What I'm finding includes:

• Fan speed doesn't seem to reflect delta between set temperature and actual temperature. My adviser told me the fan slows down if the heat exchanger isn't able to keep up. My answer: having the air moving, even slightly cooler than ambient, is better than sitting in a puddle of your own sweat. FWIW, the air seems quite cold, what little is blowing. The Benz would crank the fan to high and slow down as the preset temperature was reached. I can't honestly say I've ever noted the MS fan running at more than 7 or 8 when in Auto... Scale goes to 12 I think?
• Setting remotely never seems to get close to what is requested, even if the car is plugged in.
• Temperature setting on the screen isn't even close to what the actual temperature is - even the temperature *reported by the car to the app* doesn't match when in apparent equilibrium! Huh?? I set the Benz to one temperature in the summer and another in the winter... and never had to touch any of the HVAC controls. It just worked. Correct me if I'm wrong, but I thought that was the point of 'Auto'...
• Sometimes, a minute or two after beginning to drive, I hear the fan gently ramp down to a stop, then after a brief pause, come back up to speed (or almost up to speed). I don't know if this is normal or not, and is the reason I approached my service adviser yesterday.
• The center dash vents are noticeably weaker than the ones on the outside edges. My service adviser told me people had complained about too much air from the center vents and Tesla had re-balanced them to what I'm seeing. Not my preference... what ever happened to the dampers most cars include? I have always found that the center vents help the rear passengers more than the side vents do... because rear vents are always inadequate on their own.

It strikes me that all of this is software-controlled. It should be readily fixable. As I asked my Service Adviser, do the folks in California where the car is made find this acceptable? What about in the other sun-drenched states?

 

[mmccord]

In my experience, the 'auto' fan speed should be labeled 'insufficient'. I just end up setting the fan speed manually.

 

[mknox]

In my experience, the 'auto' fan speed should be labeled 'insufficient'. I just end up setting the fan speed manually.

Yep. I keep my right steering wheel scroll wheel set to Fan Speed and I use it a lot. I can flick it up or (rarely) down and push it to return to Auto.

- - - Updated - - -

... what ever happened to the dampers most cars include?

They are kinda hidden. You have to move the left/right control all the way to one side (forget which way) and the damper will close the vent. I'm more used to a separate control, usually below the vent itself.

 

[beeeerock]

They are kinda hidden. You have to move the left/right control all the way to one side (forget which way) and the damper will close the vent. I'm more used to a separate control, usually below the vent itself.

Yeah, I was thinking more in terms of a control to adjust air volume without re-directing it, like what I was accustomed to in my Benz.

 

[brianman]

Agree with this totally. It's not that the newer car A/C doesn't work as well (for example if I move the temp to LO it will blast cold air just like the old car) but the new car is not near as aggressive at achieving the set temperature and I will often have to move it to LO when I get in a hot car.

I liked the operation on the old car much better than the new car.

I see that you have a P85D. Do you have Range Mode on?

 

[Solarwind]

I find the same as most here, you always have to set lower then the true temp. But i am not unhappy after they fixed it, as it can be a bitch with no AC. Our compressor housing cracked and had to be replaced. Manufacture defect??