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AC performance heavily reduced in AZ heat

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Hi everyone, I’ve had my model 3 for a little over a month now and I had some questions about AC performance.
For the past couple weeks when I leave work I have noticed my Air conditioning is pretty poor. The air blowing out of the vents is definitely warmer than normal and after about 15 minutes of driving the cabin temp is still over 80 degrees. I am assuming this is because the AC is cooling the battery but there are no warnings or alerts on the screen while this is happening. After about 15 minutes the car will suddenly start blowing really cold air. It’s done this for about the past 2 weeks when I leave work. I do “precondition” the cabin for about 5 minutes before leaving. When I get in the car the ambient temperature sensor on the screen reads about 115-125 degrees and it stays that way the whole ride home. I do not use the cabin protection because I lose about 10% of charge throughout the day and it doesn’t feel any different in the car vs 5 minutes of preconditioning without it. The cabin has always gotten to about 150-160 degrees throughout the day but I am only recently noticing this reduced performance. And I don’t see how that would affect the battery temp. I guess I’m a little confused on how this battery cooling works and when it’s needed. Like is it needed only when driving? Or does it cool it all the time?
Thanks
 
Get your AC checked. It was 41.2 C (106 F) here the other day -- in the shade -- and the 3 had no trouble keeping us cool after being parked in the sun for hours, and driving it around in the heat. I just really wish the scroll wheel could adjust the fan speed like in my S since I'm a constant fan adjuster, rather than a set-it at a temperature and leave it -- because I need lots of cold air blowing on me after being out in the heat. I really like the air flow control though -- and I can blow it directly at me, while my wife who likes the heat -- can adjust her own air flow. Great system but please Tesla update the software so we can control the fan with the right scroll wheel !!
 
Thanks guys I will look into getting it checked.

I actually already use 2 sunshades back to back but I should look into a better one, they aren’t very think.

I heard the model S has a screen alert when the AC is being used for the battery. Has anyone seen than on the S or 3 before? That’s what makes me think I may need to have he car looked at because I get no warning messages.
 
If you can afford it, and willing to take the slight risk, you may want to look into ceramic tint for not only the side and back windows, but also the front windshield. In my experience it reduces the ambient temperature significantly. Now there is always risk that a police vehicle may require you to remove (e.g., fixit ticket), but I've found 80% tint on windshield and 20% tint (darker) on the windows really cuts down the heat without having to put up sun guards. If you decide this route, go ceramic...as it won't foul your telecoms. Good luck!
 
Yeah my other car has the windshield tinted and I really like it but my tint guy was too afraid to tint the front and back of this car. He said he didn’t want to ruin the electronics. And I’m not sure where to even go for the windshield since it’s illegal and either people won’t do it or they want cash. So I just got 15% on the sides. It actually doesn’t even look bad not having the back done since it’s so small but I do miss the front.

I’m not sure this should affect the AC performance though because the air coming out of the vents is warm for about 10-15 min.

I will try precooling earlier but unfortunately I don’t have access to my phone until I leave my work room and it’s about a 5 minute walk to my car.

Even if I shut the AC off at a stoplight I can still hear the condenser fan running at full speed. So the AC must be going to the battery. So either my AC is not working correctly or the model 3 cannot handle the 115-125 degree asphalt temperatures while trying to cool the cabin and battery at the same time
 
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Hi everyone, I’ve had my model 3 for a little over a month now and I had some questions about AC performance.
For the past couple weeks when I leave work I have noticed my Air conditioning is pretty poor. The air blowing out of the vents is definitely warmer than normal and after about 15 minutes of driving the cabin temp is still over 80 degrees. I am assuming this is because the AC is cooling the battery but there are no warnings or alerts on the screen while this is happening. After about 15 minutes the car will suddenly start blowing really cold air. It’s done this for about the past 2 weeks when I leave work. I do “precondition” the cabin for about 5 minutes before leaving. When I get in the car the ambient temperature sensor on the screen reads about 115-125 degrees and it stays that way the whole ride home. I do not use the cabin protection because I lose about 10% of charge throughout the day and it doesn’t feel any different in the car vs 5 minutes of preconditioning without it. The cabin has always gotten to about 150-160 degrees throughout the day but I am only recently noticing this reduced performance. And I don’t see how that would affect the battery temp. I guess I’m a little confused on how this battery cooling works and when it’s needed. Like is it needed only when driving? Or does it cool it all the time?
Thanks
I would definitely have your AC checked. I have had my 3 for three months and haven't had any issues with the AC. I have noticed that on a couple of occasions the AC blows air (not cold) for maybe 30 seconds or so before it kicks into gear. But nothing like you are reporting. For what it is worth, I also typically have the temp set at 67 and the fan speed at "7." If you turn off the air to the backseats, you will get more flow up front.

My situation may be different from yours in other situations in that my car is either in my home garage or the parking garage at work. It never sits out in the full sun. I turn on the AC with the app when I walk out of my office and by the time I get to the car (about 5 min or less) the car is icey cold.
 
I had an issue a while back where every so often, my AC compressor would cycle off and on and off an on for about a minute, before settling back on on. I knew this because I could feel the slight shudder of the compressor toggling on and off at a stoplight, and also when I brought up the climate control panel I saw the blue shading behind the AC button go on and off. I took my car to the SC, they said it was a software issue and pushed an update. It was a pretty intermittent issue but it hasn't recurred since.

When your AC system isn't cooling very well, does the AC button in the climate control settings have a shaded blue background? Or is it white?
 
Hi everyone, I’ve had my model 3 for a little over a month now and I had some questions about AC performance.
For the past couple weeks when I leave work I have noticed my Air conditioning is pretty poor. The air blowing out of the vents is definitely warmer than normal and after about 15 minutes of driving the cabin temp is still over 80 degrees. I am assuming this is because the AC is cooling the battery but there are no warnings or alerts on the screen while this is happening. After about 15 minutes the car will suddenly start blowing really cold air. It’s done this for about the past 2 weeks when I leave work. I do “precondition” the cabin for about 5 minutes before leaving. When I get in the car the ambient temperature sensor on the screen reads about 115-125 degrees and it stays that way the whole ride home. I do not use the cabin protection because I lose about 10% of charge throughout the day and it doesn’t feel any different in the car vs 5 minutes of preconditioning without it. The cabin has always gotten to about 150-160 degrees throughout the day but I am only recently noticing this reduced performance. And I don’t see how that would affect the battery temp. I guess I’m a little confused on how this battery cooling works and when it’s needed. Like is it needed only when driving? Or does it cool it all the time?
Thanks

Not sure if your issue is the same as ours. For our VIN 19xxx, picked up in early June, our AC didn't work properly; It would cool the car down fairly well...not great, but then stop cooling after 30-60 minutes and just blow warm air. Especially noticeable on long trips. Tesla looked at data logs remotely and diagnosed the compressor was losing pressure. Mobile ranger traveled out to our house and replaced the compressor in our driveway. Works great now.
 
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What temp do you have your AC set at?

I am in AZ too and I thought I had an issue with my AC but found that the M3 works different than my ICE car. In my ICE if I had the car temp set at 72, it would just cool with cold air with full blast fan until it hit that temp, then slow down the fan but still have the same temp air come out.

On my M3, I found that at 72 it produces slightly warmer air than when I have it at 65 or lower. Try setting the temp low and manually having the fan speed higher and see if that works.
 
It’s a variable speed compressor and yeah I have noticed that when it’s working correctly and you bump it up a degree the air will get slightly warmer. That’s to save energy and is normal my Audi was the same way. Rather than constantly turning the compressor on and off it will just run it constantly at reduced capacity.

Today is probably the hottest day of the year and if I have issues today I will probably ask for service. Like I said before, I can completely turn off the climate system while this is happened and the outside condenser fan is still running very loud. I left it off for about 5 minutes then I just got too hot in the car. The AC must be cooling the battery and for some reason my system does not have the capacity to cool the battery and the cabin at the same time. I will report back with today’s findings.
 
It’s a variable speed compressor and yeah I have noticed that when it’s working correctly and you bump it up a degree the air will get slightly warmer. That’s to save energy and is normal my Audi was the same way. Rather than constantly turning the compressor on and off it will just run it constantly at reduced capacity.

Today is probably the hottest day of the year and if I have issues today I will probably ask for service. Like I said before, I can completely turn off the climate system while this is happened and the outside condenser fan is still running very loud. I left it off for about 5 minutes then I just got too hot in the car. The AC must be cooling the battery and for some reason my system does not have the capacity to cool the battery and the cabin at the same time. I will report back with today’s findings.
You never did say what your temperature and fan settings are.
 
Yes! I'm in Phoenix with the same problem. Only started happening after the car was updated to 2018.26.X. What SW are you on? I've noticed that it only happens when the car sits outside all day at work. I'll go a whole weekend of frequent trips and it won't happen at all. Last week I decided to take the car to the SC to diagnose. They kept it for 4 days and finally told me its a SW problem and will be fixed in 2018.28. As you suspected, its diverting AC to the high voltage battery.

I was hoping it had something to do with Cabin Overheat Protection, since that was new in 2018.26.X, so I'm performing an experiment today where I set it to fan only. If that doesn't work, my next experiment will be with Cabin Overheat Protection fully on to AC but try not pre-conditioning via the app and just walk up to the car. Let me know if you've tried either of these.

I saw 2018.28 dropped today to a few cars so hopefully this problem will be short-lived.
 

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