TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker and becoming a Supporting Member. For more info: Support TMC
Start a Discussionhttps://teslamotorsclub.com/tmc/tags/

Did I expect too much from the HEPA filter?

Discussion in 'Model S' started by realyc, Apr 23, 2017.

Tags:
  1. realyc

    realyc Member

    Joined:
    Nov 29, 2016
    Messages:
    8
    Location:
    Bay area
    I got an S in December with the premium upgrades. The HEPA filter works great 99% of the time and I don't smell any gasoline fumes :) But whenever I inevitably follow a truck with horrible emissions that's visible as smoke, I can quickly smell that (and it's not just a little bit of smell; it actually smells horrible). Turning on bioweapon defense mode makes no difference and only makes the smell worse. I always have the A/C on, and of course, my windows/sunroof were closed.

    Is this normal with the HEPA filter or should I have Tesla check it out for leaks and stuff?
     
  2. CmdrThor

    CmdrThor Active Member

    Joined:
    Jul 24, 2013
    Messages:
    1,064
    Location:
    Marietta, GA
    Doesn't seem normal to me, I have never noticed any smell from outside with the HEPA filter and I've been near trucks puffing out some serious black smoke.
     
    • Like x 2
  3. Saghost

    Saghost Active Member

    Joined:
    Oct 9, 2013
    Messages:
    4,900
    Location:
    Delaware
    With my X with Bio, I've driven right through clouds of smoke without every smelling anything, and the couple times I did smell a bit switching into Bioweapon quickly cleared the cabin again.

    It's hard to say without actually seeing it, but it doesn't sound like yours is as effective.
     
  4. brkaus

    brkaus Active Member

    Joined:
    Jul 8, 2014
    Messages:
    2,541
    #4 brkaus, Apr 23, 2017
    Last edited: Apr 23, 2017
    HEPA filters will filter particles down to some small size. That would cover bacteria and virus particles. Hence the bio weapon marketing name.

    HEPA won't filter vapors or gasses. They do add charcoal filters to help with odors and vapors. Not sure the effectiveness of a carbon filter or lifetime of such a filter. I feel like bioweapon mode may actually allow more vapor type pollutants to pass as carbon filtering depends on contact time and running the fan in high would decrease contact time.

    Of course my knowledge is only based on what I have read about air filters for allergies and carbon filters used in aquarium filtration :)
     
    • Informative x 3
    • Like x 2
  5. realyc

    realyc Member

    Joined:
    Nov 29, 2016
    Messages:
    8
    Location:
    Bay area
    Thanks guys! I'll see if I can get Tesla to take a look.
     
  6. Haxster

    Haxster Member

    Joined:
    Apr 4, 2016
    Messages:
    602
    Location:
    Silicon Valley
    I'm still trying to figure out if there's a way to bypass the regular HEPA filters when the A/C is on.

    Sometimes, when you cut a really good one, you want to relish it for a while; or even share it with others in the car. With the HEPA filters, it's often gone before you can take your first sniff.
     
    • Funny x 17
    • Like x 1
  7. one5n1neSDoo

    one5n1neSDoo Member

    Joined:
    Jun 28, 2016
    Messages:
    75
    Location:
    SFO
    ^ wow. Just wow.
     
    • Like x 2
    • Funny x 1
  8. brkaus

    brkaus Active Member

    Joined:
    Jul 8, 2014
    Messages:
    2,541
    I don't think the HEPA is in the loop when the car is on recirculate. But I haven't taken mine apart yet to look. I think recirc is the solution to your "problem."
     
    • Like x 2
  9. oktane

    oktane Active Member

    Joined:
    Oct 25, 2016
    Messages:
    1,510
    Location:
    USA
    Biodefense is a bit of an exaggeration and marketing ploy. The only thing it does is turn the fan on high, sucking intake from a large HEPA filter and creating a positive-pressure environment in the cabin. Theoretically this will keep dirt particles etc. from getting through the sloppy door and window seals.

    When you turn BDM on, it will actually INCREASE the amount of outside air and gases being forced into the cabin. The outside air may contain volatile compounds found in exhaust that may not be particulate but certainly can stink. Theoretically allergens will be trapped by the filter, however, and it is quite large.

    Finally, if you remove your frunk and disassemble the HEPA filter, you might notice that the seal between the filter and cabin intake is very flimsy and perhaps installed incorrectly. I took mine apart and the seal (which is just a piece of adhesive weather stripping) was totally folded over onto itself, effectively bypassing the HEPA filter and allowing unfiltered air into the cabin. It was an easy fix, but evidence of very poor and cheap design for a forced-air filter.

    Good luck.
     
    • Helpful x 2
    • Informative x 2
  10. Saghost

    Saghost Active Member

    Joined:
    Oct 9, 2013
    Messages:
    4,900
    Location:
    Delaware
    Bioweapon isn't just a large HEPA filter, there are also activated carbon layers for both acid and alkaline which should prevent anything that can react/stink from reaching the cabin if the system is working correctly.
     
  11. boaterva

    boaterva Supporting Member

    Joined:
    Apr 2, 2016
    Messages:
    2,906
    Location:
    Northern Virginia, USA
    But the general consensus, which is not clear from the Tesla website, is that all cars have the carbon canisters and that they are part of normal airflow (as well as BDM). Correct me if I'm wrong, but that's what I've gathered from TMC.
     
  12. malcolm

    malcolm Active Member

    Joined:
    Nov 12, 2006
    Messages:
    2,604
    Bioweapon Enhance Mode - locks windows and switches the stereo to Brown Noise.
     
    • Funny x 1
  13. Saghost

    Saghost Active Member

    Joined:
    Oct 9, 2013
    Messages:
    4,900
    Location:
    Delaware
    I don't think so - or at least they aren't the same. I just got a P85+ loaner this morning, and I definitely smelled a skunk in it that I was completely unaware of on my drive up. It's possible that it was hit in the half hour in between, but I never smell them in my X.
     
  14. croman

    croman Active Member

    Joined:
    Nov 21, 2016
    Messages:
    1,820
    Location:
    Chicago, IL
    All refresh cars have the carbon filter(s) I think.
     
    • Informative x 1
  15. Saghost

    Saghost Active Member

    Joined:
    Oct 9, 2013
    Messages:
    4,900
    Location:
    Delaware
    I don't know one way or the other, but I'd be surprised if they have the exact same filters.

    The Bioweapon ones are presumably designed to sit behind the HEPA - meaning they can have very small pore for maximum surface area without risking being choked up, since anything large will be stopped by the HEPA.

    In the other cars I believe it's the only filter, so I'd think dust would quickly block up a filter optimized for the Bioweapon role.

    But as I said, I don't know for certain - it's possible that Tesla chose a less optimized filter that they could use for both for some reason. Maybe we can get part numbers for both versions of the smaller filter as installed and see if they match?
     
  16. boaterva

    boaterva Supporting Member

    Joined:
    Apr 2, 2016
    Messages:
    2,906
    Location:
    Northern Virginia, USA
    I think it's the other way round.... the HEPA is the microfilter, and the carbon is more of the 'odor' absorber and doesn't really filter pollen or anything. Think Dr Scholls. :)

    A good question is: what size particulate *does* a none HEPA car filter?

    And I was thinking of recent cars, of course, not P85+ vintage, sorry...
     
  17. J1mbo

    J1mbo Member

    Joined:
    Aug 20, 2013
    Messages:
    973
    Location:
    UK
    I thought this is what the ventilated seats are for?
     
    • Funny x 2
  18. realyc

    realyc Member

    Joined:
    Nov 29, 2016
    Messages:
    8
    Location:
    Bay area
    OP here - I got my car back from Tesla service. They unfortunately didn't find anything wrong with my HEPA filter after checking out the filter and doing tests (wonder what that means). Two strange things:
    - The service person said with confidence that having A/C on but not BDM bypasses the filter, and I thought many of us believe that standard A/C uses the HEPA too.
    - My cabin air quality seems to have gotten even worse after the service o_O
     
  19. oktane

    oktane Active Member

    Joined:
    Oct 25, 2016
    Messages:
    1,510
    Location:
    USA
    It's a scam like everything else. Over promise and under deliver. As clean as an operating room.... lol.
     
  20. ICUDoc

    ICUDoc Member

    Joined:
    May 19, 2015
    Messages:
    566
    Location:
    Sydney NSW
    When I activate BDM, I am UNABLE to smell anything from outside. But I never adjust the settings ie turn AC on or off or whatever in BDM- I just let it do its thing...
    regards
     

Share This Page