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Hey Guys

I am curious to know how the bio weapon filter works in the MX. Does the filter only filters the air coming from out side or does it also filters the air with in the cabin. A few days ago, I order fast food and turned on the bio weapon to filter out the food odours but I couldn't tell if it was working or not. Any body have any clue on how it works?

Thanks
 
Have you seen that posted/described anywhere or taken apart your S to know for certain? I ask for a couple reasons. First, when going into bioweapon defense mode, the system automatically selects the recirculation mode. Second, I've looked for any definitive source AND I've asked my service center who ultimately said they weren't even sure. I've seen the picture on these forums of the HEPA filter placement (just behind our frunk) but couldn't tell from the picture alone whether that was purely intake to the vehicle or also used in any recirculation. I also haven't been able to find any definitive source on how/where the smaller filter and carbon filters are used.

You may be 100% right so please don't take offense at my questions. Too many others, including my SC, have speculated but later said they didn't really know so I'm just looking for something more certain. Thanks.
 

Saghost

Well-Known Member
Oct 9, 2013
8,224
7,091
Delaware
It's not possible to build the positive pressure that Bioweapon strives for without outside air - you need more total air in the cabin than you had before.

Because of this, Bioweapon can't use pure recirculation. Your post is the first suggestion I've seen that it might use any recirculation, and I still don't understand how that would be helpful to the goals of the operating mode.

Where do you see it selecting recirculation? It's been a while since I used Bioweapon, but the way I remember it, it greyed out both outside and recirculate when I hit Bioweapon, which is on the same line.
 
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ecarfan

Well-Known Member
Moderator
It's not possible to build the positive pressure that Bioweapon strives for without outside air - you need more total air in the cabin than you had before
I agree. Elon has stated that Bioweapon mode creates positive pressure in the cabin. It has to draw a significant quantity of air into the cabin -- through the HEPA filter -- to achieve positive pressure. Just because the display shows recirculation as being "on" does not mean that no additional air is being brought into the cabin in Bioweapon mode.
 
I agree with the comments about positive pressure but I believe there's more to it than that. For example, can anyone definitively describe the path that air takes to go through the smaller air filter? Does *only* recirculated air go through the smaller filter or ??? When/How does the smaller filter come into play?

Do people think that all the "dirty" air is simply pushed out of the car via positive pressure? Wouldn't it make more sense that SOME of the air inside the car also goes through the HEPA filter, via recirculation? Wouldn't that also explain the fan being on high when in bioweapon defense mode? That is purely speculation on my part, but I mention the possibility because it seems reasonable and I've still not seen anything which definitively describes how the different filters work together and which "path" air can take to go through any one or all filters.
 

Saghost

Well-Known Member
Oct 9, 2013
8,224
7,091
Delaware
I agree with the comments about positive pressure but I believe there's more to it than that. For example, can anyone definitively describe the path that air takes to go through the smaller air filter? Does *only* recirculated air go through the smaller filter or ??? When/How does the smaller filter come into play?

Do people think that all the "dirty" air is simply pushed out of the car via positive pressure? Wouldn't it make more sense that SOME of the air inside the car also goes through the HEPA filter, via recirculation? Wouldn't that also explain the fan being on high when in bioweapon defense mode? That is purely speculation on my part, but I mention the possibility because it seems reasonable and I've still not seen anything which definitively describes how the different filters work together and which "path" air can take to go through any one or all filters.

The cabin has normal exhaust vents designed into it (at the rear under the bumper,) and leaks at the seals. It's probably faster to clear the cabin by pushing air out through all of those than by recirculating the cabin air - especially since recirculating would lead to dead zones unless it is design very carefully.
 
It's probably faster . . . especially since recirculating would lead to dead zones unless it is design very carefully.
You seem to be implying that you'll get fewer or no dead zones by just pushing air into random leaks at seals and/or explicit exhaust vents, and your use of "probably" also implies more speculation. Tesla has developed something fantastic here; I just wish they'd share a bit more of the details. One of these days I hope to get time with one of the technicians who might know for certain.
 

BerTX

Active Member
Supporting Member
May 2, 2014
3,505
3,654
Texas/Washington
I agree with the comments about positive pressure but I believe there's more to it than that. For example, can anyone definitively describe the path that air takes to go through the smaller air filter? Does *only* recirculated air go through the smaller filter or ??? When/How does the smaller filter come into play?

Do people think that all the "dirty" air is simply pushed out of the car via positive pressure? Wouldn't it make more sense that SOME of the air inside the car also goes through the HEPA filter, via recirculation? Wouldn't that also explain the fan being on high when in bioweapon defense mode? That is purely speculation on my part, but I mention the possibility because it seems reasonable and I've still not seen anything which definitively describes how the different filters work together and which "path" air can take to go through any one or all filters.

Reading the May 2, 2016 Tesla blog about the system, it looks like you may be right. (bolding is mine)

" Inspired by the air filtration systems used in hospitals, clean rooms, and the space industry, we developed a HEPA filtration system capable of stripping the outside air of pollen, bacteria, and pollution before they enter the cabin and systematically scrubbing the air inside the cabin to eliminate any trace of these particles."
 
Reading the May 2, 2016 Tesla blog about the system, it looks like you may be right. (bolding is mine)

" Inspired by the air filtration systems used in hospitals, clean rooms, and the space industry, we developed a HEPA filtration system capable of stripping the outside air of pollen, bacteria, and pollution before they enter the cabin and systematically scrubbing the air inside the cabin to eliminate any trace of these particles."

Does it make sense to turn on the Bioweapon mode when you first get into the cabin, leave it on for x number of minutes, then switch to recirculating mode?
 
Does it make sense to turn on the Bioweapon mode when you first get into the cabin, leave it on for x number of minutes, then switch to recirculating mode?
If you have bioweapon defense mode, all outside air is coming through the HEPA filter anyway. Turning on Bioweapon defense mode when you don't feel a need probably won't benefit you. That having been said, many people say recirc isn't necessarily advisable regardless, as the carbon dioxide you produce by breathing will build up. Regulations may reduce that by requiring some air to always come from the outside, but you'll also notice that Auto typically doesn't use recirc for some reason. On the flip side of that same coin, I'm told that recirc is used by Auto if you put the vehicle in Range Mode. This would seemingly support the argument that recirc isn't dangerous (regardless of whether or not one should consider the space between dangerous and healthy here).
 
If you have bioweapon defense mode, all outside air is coming through the HEPA filter anyway. Turning on Bioweapon defense mode when you don't feel a need probably won't benefit you. That having been said, many people say recirc isn't necessarily advisable regardless, as the carbon dioxide you produce by breathing will build up. Regulations may reduce that by requiring some air to always come from the outside, but you'll also notice that Auto typically doesn't use recirc for some reason. On the flip side of that same coin, I'm told that recirc is used by Auto if you put the vehicle in Range Mode. This would seemingly support the argument that recirc isn't dangerous (regardless of whether or not one should consider the space between dangerous and healthy here).
 

mjptech

Being cyberbullied by TMC users PhilDavid + DCEV
Mar 30, 2019
532
245
Ventura
Thanks so much. Very helpful. What exactly does the bioweapon defense mode do if all the air is going through the HEPA filter anyway?

For the most part, Bioweapon Mode is basically a "let's speed this filtration process up" - in extreme cases, such as entering a wildfire zone or smoke-filled area. It will help push the stale air away, like when you're on a plane.

In the end, the filtration does what most vehicles do... it just includes a charcoal filter as well to help...
Tesla “Bioweapon Defense Mode” As Effective as a 2010 Mazda?
 
Yes, that is what is happening right now in California. The smoke is terrible. So, it still seems to me that when we first enter the cabin, we could start with the bioweapon mode to “speed the filtration process up“. Then, after X number of minutes, we could turn it back to the auto mode. The question is, how many minutes?
 

mjptech

Being cyberbullied by TMC users PhilDavid + DCEV
Mar 30, 2019
532
245
Ventura
When I turned mine on, I noticed the air volume coming from the vents was decreased. Fan was on high, just lower volume than when bioweapon turned off. Normal?

Yes - when Bioweapon is turned on, it's combining air recirculation with fresh (or, whatever the outside air is), so the air volume goes down, even though the workload goes up (I believe some of the air is getting redirected before it hits the vents).

Probably need to check with the air flow paths that were recently posted when someone's AC stopped blowing air in the X (I actually had this problem the past few weeks after my service update - no air flow in the rear center or the third row pillars - turned out they pinched the "snorkel" as they call it in the center console when replacing the USB ports)..
 
Yes - when Bioweapon is turned on, it's combining air recirculation with fresh (or, whatever the outside air is), so the air volume goes down, even though the workload goes up (I believe some of the air is getting redirected before it hits the vents).

Probably need to check with the air flow paths that were recently posted when someone's AC stopped blowing air in the X (I actually had this problem the past few weeks after my service update - no air flow in the rear center or the third row pillars - turned out they pinched the "snorkel" as they call it in the center console when replacing the USB ports)..



Yes, I was going to look into that as well - I noticed my used 2017 vents aren't working in the rear as I expect they should.
 
it just includes a charcoal filter as well to help...
What about this Elon Musk Twitter post? I understand that at one point some people put a HEPA filter in and got the service center to enable the feature, but that doesn't prove those items don't exist on vehicles where the upgrade was paid for (or perhaps even in early vehicles without the feature, like with the larger battery in the Model S 60). Also, having previously driven other vehicles with air filters that have carbon in the air filter, I can assure you that my Model X does FAR better than they ever did at dealing with sewage and skunk smells, which wouldn't necessarily be measured in many tests. This could be due to having an actual bed of carbon instead of just a thin layer on the filter, or it could be the work of these other components.
 

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