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Miraculous air conditioning

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Huh. I've never had an ICE that could do that, and I don't understand how they managed it.

Beats me how they did it, but it was an '09 Cadillac CTS and Remote Start worked great. One thing I liked about the Caddy was that if it was hot, in addition to the a/c, it would automatically turn on the seat coolers. In the winter, it would automatically turn on the defrosters and seat heaters by itself too. I didn't do it a lot because I didn't really like the thought of an ICE idling like that.
 
I do understand all of that, and it makes sense... except that my former ICE would have the cabin cooled down in exactly the same amount of time under the same conditions when I used Remote Start, but without all the racket.
Huh. I've never had an ICE that could do that, and I don't understand how they managed it.
I'd say the compressor in the ICE in question was properly sized. As I stated earlier in this thread, I think the system in the X is underpowerd. The fact that they can run it harder without relying on engine speed (possibly paired with testing mainly in mild CA) may have allowed them to undersize it, necessitating the higher noise level when it runs (especially in the real world).
 
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I'd say the compressor in the ICE in question was properly sized. As I stated earlier in this thread, I think the system in the X is underpowerd. The fact that they can run it harder without relying on engine speed (possibly paired with testing mainly in mild CA) may have allowed them to undersize it, necessitating the higher noise level when it runs (especially in the real world).

Most of the noise under discussion is from the fans pulling air through the condenser cores, which the ICE car has to do just as much, if not more (because the engine radiator increases the pressure drop across the core set.)
 
For those who might find the AC not up to par, try using "AUTO" for all settings. I have seen many review and test drive videos recently and 90% of the time, the temp is set to "LO" which drives me nuts. People set the temp to LO assuming that's the coldest (and technically it is), but when you set to LO in AUTO mode, it kicks the fan on high so then they turn the fan down because it's too loud. So, now, the compressor is working hard but the cabin isn't cooling efficiently because there is not enough air flow. My philosophy is to keep everything in AUTO and adjust the fan using the temperature control. When I enter a super hot car, I turn the temp up to 75 which keeps the fan at a fast but reasonable speed. Once the car starts to cool down, but with 75 being too warm, I gradually lower the temperature until I get to 72 where I'm most comfortable. This way, the fan never gets too high. This is the most efficient way to use the system. The AUTO setting is designed for efficiency and comfort. Trust it. Using LO temp with manual fan speed wastes energy and doesn't cool the cabin properly.
 
IAs I stated earlier in this thread, I think the system in the X is underpowerd.

Everything I've read and heard prior is that it is actually quite a powerful unit.... because it has to cool both the cabin and the battery coolant loop. For whatever reason, my 2018 X 100D seems just fine to me. Plenty cold and none of the weird cut-outs as other describe. And we have had some mighty hot and humid weather this summer.

Most of the noise under discussion is from the fans pulling air through the condenser cores, which the ICE car has to do just as much, if not more (because the engine radiator increases the pressure drop across the core set.)

Not completely. My former 2013 S's compressor was so loud I could not only hear it, but feel it in the seats and the steering wheel when it spooled up. I used to use "Range Mode" simply to keep it a bit quieter. Tesla applied a TSB "fix" consisting of new isolation mounts and some sort of "acoustic blanket" over the compressor. It helped a little bit.

I can hear, and sometimes feel the compressor in my new X too. But yeah, the condenser fans out front are loud too. My recent ICE cars all had electric radiator/condenser fans as well, but they were not as loud as Tesla's for some reason.... and they had to cool a hot ICE's cooling system as well.
 
Huh. I've never had an ICE that could do that, and I don't understand how they managed it.
My previous ICE without cabin overheat protection or remote start cooled as well or better than the X does with it when I forget to precondition even though it has overheat protection on. In either case, I would open the windows to let out excess heat when I first started to drive. The only difference that might make sense is that my previous vehicle were all sedans and perhaps had less hot in-cabin surface area to counter.
For those who might find the AC not up to par, try using "AUTO" for all settings. I have seen many review and test drive videos recently and 90% of the time, the temp is set to "LO" which drives me nuts. People set the temp to LO assuming that's the coldest (and technically it is), but when you set to LO in AUTO mode, it kicks the fan on high so then they turn the fan down because it's too loud. So, now, the compressor is working hard but the cabin isn't cooling efficiently because there is not enough air flow. My philosophy is to keep everything in AUTO and adjust the fan using the temperature control. When I enter a super hot car, I turn the temp up to 75 which keeps the fan at a fast but reasonable speed. Once the car starts to cool down, but with 75 being too warm, I gradually lower the temperature until I get to 72 where I'm most comfortable. This way, the fan never gets too high. This is the most efficient way to use the system. The AUTO setting is designed for efficiency and comfort. Trust it. Using LO temp with manual fan speed wastes energy and doesn't cool the cabin properly.
This advice may be good for some and was certainly good to post, but the problem with AUTO on the air direction is that it leaves hot spots (at the very least foot wells don't get cooled in AUTO). I believe I pointed this out (and hypothesized that the people who are happy with the system are basing it on the air they feel blowing on them vs the actual temperature of most of the air in the cabin) earlier in the thread. I pretty much always use auto for everything except air direction, and I'm pretty much always uncomfortable when it's hot outside including when air direction IS set to AUTO because the system got so far behind while air direction was set to foot wells in addition to main vents (and as I believe I also stated in an earlier post on this thread, this appears to be a known limitation, because the MCU even says "limited by settings" prior to the system getting behind).
 
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...but the problem with AUTO on the air direction is that it leaves hot spots (at the very least foot wells don't get cooled in AUTO). I believe I pointed this out (and hypothesized that the people who are happy with the system are basing it on the air they feel blowing on them vs the actual temperature of most of the air in the cabin) earlier in the thread.

Good point. I have always felt that Auto in both my Model S and Model X keep the fan speed a bit too slow. Summer and Winter. Seems slower than other car's I've owned. I have my right steering wheel scroll wheel set to "Fan Speed". so that I can manually bump it up a bit if needed. A press on the scroll wheel will put the fan back in Auto. Note that I don't "blast it on me" but just up the fan speed a bit to aid in air circulation.
 
Good point. I have always felt that Auto in both my Model S and Model X keep the fan speed a bit too slow. Summer and Winter. Seems slower than other car's I've owned. I have my right steering wheel scroll wheel set to "Fan Speed". so that I can manually bump it up a bit if needed. A press on the scroll wheel will put the fan back in Auto. Note that I don't "blast it on me" but just up the fan speed a bit to aid in air circulation.

Upping the fan speed is good. Where I have a problem is when people turn the temperature way down AND lower the fan speed at the same time. This leaves a lot of the "coldness", on which the compressor worked hard to create, at the evaporator and not into the cabin.
 
We just picked up our X yesterday in the Phoenix area (hot). The AC doesn’t cool the X nearly as well as the S. I have to keep the X temperature about 5 degrees cooler than the S in order for the temperature to feel similar. Plus I have to manually control the rear AC as it won’t run unless occupants are detected in the rear seats. I’m glad the S is my daily driver while my wife drives the X. She likes it to be unreasonably warm anyway.
 
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We just picked up our X yesterday in the Phoenix area (hot). The AC doesn’t cool the X nearly as well as the S. I have to keep the X temperature about 5 degrees cooler than the S in order for the temperature to feel similar. Plus I have to manually control the rear AC as it won’t run unless occupants are detected in the rear seats. I’m glad the S is my daily driver while my wife drives the X. She likes it to be unreasonably warm anyway.

you need tint.
 
We just picked up our X yesterday in the Phoenix area (hot). The AC doesn’t cool the X nearly as well as the S. I have to keep the X temperature about 5 degrees cooler than the S in order for the temperature to feel similar. Plus I have to manually control the rear AC as it won’t run unless occupants are detected in the rear seats. I’m glad the S is my daily driver while my wife drives the X. She likes it to be unreasonably warm anyway.

Any chance you have range mode turned on? The AC on our X works just as well as our S did.
 
Soooo - I am a Newbie MX owner since June. I live in the great state of Texas. I have been three years in this state after living in the NE Snow belt all my life. I knew I wanted to move to somewhat warmer climate - but I have to admit - I really did not understand hot weather. It gets up to about 105 Degrees and just sort of stays there June-August. I found I scurry like a rat from AC to AC. One aspect of this car I have come to truly love is the ability to turn on the AC while the car is still in the garage before I go out, and then either leave the AC on when I pop into a place, or turn it on before I leave the restaurant. I put a colored note in my wallet behind my primary credit card that is RED and says "Cool Car" so I remember to turn off the AC in the car when I pull out the card to pay the bill.

The other day they started road work our street and my wife will not let me drive the MX on the oiled road. So I had to drive the old (3 years) ICE Volvo out to dinner. Having to get into a hot , hot car after dinner was no fun (not to mention continually turning on the wipers when shifting gears). And to think that Volvo car was the "Good" car just 4 months ago. Not quite sure why we kept it, it has been out of the garage about 3 times in the last 4 months -and it is a lot of car to just keep as a spare...
 
There seems to be such a mix of feelings about the MX air-con, ranging from amazing to very poor. I would rate our MX (2018 7-seater) air-con as very effective and of course the ability to remotely control the car climate is a huge bonus. But there seems to be a lot of people on the forums having issues with their fans, airflow and temperature, so sounds like inconsistent build quality yet again. But I don't think the design is inherently poor, otherwise nobody would be happy with the results.
 
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There seems to be such a mix of feelings about the MX air-con, ranging from amazing to very poor. I would rate our MX (2018 7-seater) air-con as very effective and of course the ability to remotely control the car climate is a huge bonus. But there seems to be a lot of people on the forums having issues with their fans, airflow and temperature, so sounds like inconsistent build quality yet again. But I don't think the design is inherently poor, otherwise nobody would be happy with the results.

1. They probably are not using AUTO mode.
2. They probably have RANGE MODE on.

Best AC performance is with AUTO on and range mode OFF.
 
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1. They probably are not using AUTO mode.
2. They probably have RANGE MODE on.

Best AC performance is with AUTO on and range mode OFF.

Possibly, but you do hear of issues with missing ducting, dodgy seals etc. which could seriously affect the system performance. FWIW I just keep everything on Auto and never use range mode. Compared to other cars I've owned I find it a very good system and the kids in the back are always happy too. We had a very hot summer here in the UK (often 30+ degC with high humidity) without any issues at all.

One of the reasons I went with the 7-seater option was for the upgraded rear HVAC system, which I read was very marginal for rear passengers in the base 5-seater. But I never tested them back-to-back to verify.
 
Last month I took my 100D "S" on a long road trip from east to west coasts (10,000 miles) and out west Arizona and California I experienced my air conditioner struggling and blowing hot air every once and a while. It would only last for a minute or two and then go back to cold.. Could that be a compressor starting to fail ??
Had similar issue with our S a time or two. Led me to research here on TMC for some examples and solutions. There was mention of a faulty connection coincides with the movement of the air suspension.