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HVAC Fresh Air Behavior

Discussion in 'Model S: User Interface' started by scaesare, Dec 7, 2013.

  1. scaesare

    scaesare Active Member

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    More interesting observations about the HVAC UI behavior. Last time it was the Defroster Vent. This time it's the Fresh/Recirculating setting...

    It appears that even if you disable the "Auto" setting in the control panel, and explicitly set the system for Recirculating air, as seen here:
    IMG_20131206_150204_480.jpg

    The system will occasionally decide to switch to Fresh Air mode, as seen here:
    IMG_20131206_150112_263.jpg

    It will switch over for a couple of minutes every so often in some circumstances and then switch back. I assume it's when it detects sufficient humidity in the cabin. I can hear the vent noise change, so it's not just a UI thing.

    It's not a deal breaker... but I'm not sure shy if you are going to present me with an Auto mode and an option to override it, then why not really allow me to over ride it?
     
  2. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Modern cars have a tendency to switch to outside air every chance they get. Some switch to outside every time they start up. I wasn't able to find any regulations (though I didn't look that long) but I suspect there are some because ICE cars are dangerous in ways other than the volatile fuel that they use.
     
  3. apacheguy

    apacheguy Sig 255, VIN 320

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    Study came out recently suggesting that we all drive with recycled air whenever possible. Researchers determined that it reduces pollution levels as much as 80% especially on freeways. Apparently automakers aren't on the same page.
     
  4. Chipper

    Chipper Active Member

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    Not doubting your study, but I am curious how recirculating cabin air cuts down on pollution, especially by 80%. Anyone care to elaborate??
     
  5. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    Well, it would certainly cut down on pollution if there was a smelly diesel car or truck in front of you. However, a car's interior has lots of VOCs, so it might just be trading one form of pollution for another.
     
  6. Chipper

    Chipper Active Member

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    CLICK!!! Did apacheguy mean it would cut down on pollution we are breathing??? I thought he meant using recirculated air would cause our vehicles to create less pollution in our environment. OK...making more sense now.
     
  7. apacheguy

    apacheguy Sig 255, VIN 320

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  8. kendallpb

    kendallpb Model S: P 8061

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    I've never noticed this or heard or heard a noise, but I have noticed that using the app to turn on the HVAC always (annoyingly) resets all settings to auto. I almost never want outside air (which is rarely "fresh," given all the gas-powered cars around me).

    I have noticed that the fan occasionally gets into this mode where it fluctuates a lot; next time that happens, I'll try to remember to check the icon to see if it's flipping between outside/recirc air! I have noticed that on outside air, the fan generally seems to run lower (i.e., with fan on auto, switching from outside to recirc makes the fan blow stronger).

    All in all, I find modern car "auto" settings kinda wacko. ;-)
     
  9. loganss

    loganss Spaceman

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    Yup I've noticed this too. I thought i was going crazy at first and kept toggling auto and the two air options. Very strange behavior to me.
     
  10. scaesare

    scaesare Active Member

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    Interestingly, it did it almost the entire hour ride in for me this morning, rarely cycling back to the non-recirc position. getting behind a slow salt truck and smelling fumes whether you like it or not is annoying.

    I don't mind an intelligent auto-mode. I just believe that if they give you an option to enable/disable "Auto" in the UI, then they should honor that.
     
  11. scaesare

    scaesare Active Member

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    For the heck of it, i just emailed Ownership with a request to change this behavior, as well as the defroster vent behavior as I referred to at the beginning of this thread...
     
  12. rlang59

    rlang59 Member

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    I noticed this behavior a while ago. Funny thing is that it seems to stop happening if you put the vets on foot and window and not on face. Now I haven't tested that fully so don't hold me to it.
     
  13. scaesare

    scaesare Active Member

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    I have another thread (HERE) where I discuss that enabling the Windshield Vent also activates the air conditioning compressor regardless of whether you have A/C set for on, off, or Auto. I suspect that's why the car is making a different decision about the re-circulation setting...
     
  14. rlang59

    rlang59 Member

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    That may be the case but from what I have seen you need the foot AND windshield for the re-circulation to stay on.
     
  15. scaesare

    scaesare Active Member

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    Interesting... I had all 3 on, and immediately noticed the A/C compressor kick in, so I never explored further....
     
  16. scaesare

    scaesare Active Member

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    Well looky there... I got a reply from Tesla on the email. He said it's been forwarded to the head of their HVAC engineering team, and they are looking at it already based on some similar feedback.

    His expectation is that the behavior will be changed in a future FW upgrade. I thanked him, and referred to the A/C compressor and windshield vent behavior as well...

    Nice to have a personal response with actual detail, as opposed to a canned form letter.
     
  17. kendallpb

    kendallpb Model S: P 8061

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    Great! Thanks for contacting us and letting us know the good news.
     
  18. kendallpb

    kendallpb Model S: P 8061

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    I've been noticing the annoying "pull in fresh even though he set it to recycle" thing more and more lately, perhaps because it seems to only happen on heat (on cool, in the summer, I never noticed it...and I hate the smell of exhaust and would've noticed) . . . but something I noticed a couple of times recently, related to what you say here--I changed the vents from auto (it was just on my feet) to feet+windshield and almost immediately, it reverted to recycle. This, coupled with your experience, makes me think that either of these fixes it -- (a) combining feet+something or (b) moving vents from auto to manual -- not sure which it is.

    I haven't tested either--tough to test when it is kinda random!

    I also noticed that turning the temp down so it started blowing cool air seemed to "fix" it which is absurd, of course. But I'm hoping the "vents on manual" (or "vents including something other than feet") thing works as a work-around. I may just leave it like that and see if it ever blows exhaust at me again. ;-)
     
  19. cinergi

    cinergi Active Member

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    I'm one of those other reports. I emailed ownership several days ago. They sent it to service who called and I clarified and we agreed it sounded like a software bug and they'd send it to engineering.
     
  20. scaesare

    scaesare Active Member

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    Good deal, thanks Cinergi.
     

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