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MX HVAC issue...

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Hello all,

Just wanted to ask if other MX owners have the same “issue” with MX’s HVAC:

When it is cold outside (below 30F), in other luxury brand cars, you turn the heat to Auto and most of warm air goes to your feet area and some to the trunk of the body and I feel pretty comfortable even with temp set to 67F. When driving my wife’s P90D MX (SN16k), I always feel cold in the body trunk unless I change the HVAC setting from AUTO to increase fan speed above 10. However, then it uses up the battery like crazy.

Please let me know if anyone else experiences the same in MX.

Thank you
 
Hello all,

Just wanted to ask if other MX owners have the same “issue” with MX’s HVAC:

When it is cold outside (below 30F), in other luxury brand cars, you turn the heat to Auto and most of warm air goes to your feet area and some to the trunk of the body and I feel pretty comfortable even with temp set to 67F. When driving my wife’s P90D MX (SN16k), I always feel cold in the body trunk unless I change the HVAC setting from AUTO to increase fan speed above 10. However, then it uses up the battery like crazy.

Please let me know if anyone else experiences the same in MX.

Thank you
I've noticed lately that my X will blow cold air even if the cabin temp is set to 70 and it's cold outside. It's just too inconvenient for me to take to Tesla to have it looked at.

Is your wife's X blowing cold air instead of heated air before you increase the fan speed?
 
I've noticed lately that my X will blow cold air even if the cabin temp is set to 70 and it's cold outside. It's just too inconvenient for me to take to Tesla to have it looked at.

Is your wife's X blowing cold air instead of heated air before you increase the fan speed?

It is not that it is blowing cold air, just not keeping up in AUTO mode and middle part of my body is always cold when driving the car.
 
Compared to the "auto" setting in my 2009 Tahoe, the HVAC in the Tesla is crap. There I said it.
I have to set it to 76, when 72 in the Tahoe is fine. (winter)
I have to set it to 65, when 72 in the Tahoe is fine. (summer)

I'm aware the Tahoe has a 5.3L unlimited heat source with a 350HP engine attached to the A/C compressor, and the other one is a window unit attached to some AA batteries.

Rant Over :)

To solve your issue: precondition the car every chance you get. Ideally when it's plugged in.
Whip out your iphone, and turn on the car's HVAC 10-20 min before you get in it.
 
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I've done some pretty extensive testing in pretty extreme conditions (30 degrees below zero). Originally, the auto heat setting was worthless, however a few updates back it seems as if Tesla recalibrated it. Are you running on recent firmware?

Another thing I found is the huge windshield above your body lets a considerable amount of cold air basically "fall" into your lap making your legs and torso uncomfortable. I found installing the sun shade creates enough of an insulation barrier that it makes a very noticeable difference. Certainly worth a try for you.

Originally I would have to set my fan speed to 9 (anything higher turns on recirculate and fogs the windows) and my temperature to 78 to try and stay comfortable. Now I just leave it set to Auto and 69 or 70 and it's been comfortable, even in 20 below weather.
 
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I've done some pretty extensive testing in pretty extreme conditions (30 degrees below zero). Originally, the auto heat setting was worthless, however a few updates back it seems as if Tesla recalibrated it. Are you running on recent firmware?

Another thing I found is the huge windshield above your body lets a considerable amount of cold air basically "fall" into your lap making your legs and torso uncomfortable. I found installing the sun shade creates enough of an insulation barrier that it makes a very noticeable difference. Certainly worth a try for you.

Originally I would have to set my fan speed to 9 (anything higher turns on recirculate and fogs the windows) and my temperature to 78 to try and stay comfortable. Now I just leave it set to Auto and 69 or 70 and it's been comfortable, even in 20 below weather.

Thank you for the reply.
I am running the latest firmware.
I also have the top half of the windshield covered with ceramic film that creates the same layer of protection as the sun shade you mentioned.
but may be asSabrToothSqrl mentioned, the HVAC may be substandard.https://teslamotorsclub.com/tmc/members/sabrtoothsqrl.30605/
 
Compared to the "auto" setting in my 2009 Tahoe, the HVAC in the Tesla is crap. There I said it.
I have to set it to 76, when 72 in the Tahoe is fine. (winter)
I have to set it to 65, when 72 in the Tahoe is fine. (summer)

I'm aware the Tahoe has a 5.3L unlimited heat source with a 350HP engine attached to the A/C compressor, and the other one is a window unit attached to some AA batteries.

Rant Over :)

To solve your issue: precondition the car every chance you get. Ideally when it's plugged in.
Whip out your iphone, and turn on the car's HVAC 10-20 min before you get in it.

I love my Model X but I'd agree with this about AC/ Heat. I typically have to use the App 10-15 minutes before I arrive to my car to be comfortable many times.
 
Thank you for the reply.
I am running the latest firmware.
I also have the top half of the windshield covered with ceramic film that creates the same layer of protection as the sun shade you mentioned.
but may be asSabrToothSqrl mentioned, the HVAC may be substandard.

The extra layer of film will block light, but it does not create insulation. The Tesla sun shade is not tight against the glass, thus creating a pocket of air between the glass and the sun shade. That pocket of air is what insulates the cabin from the cold windshield.