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Tesla X HEPA Filter retrofit

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....and nor is the rest of the car air tight. The 'demo' Tesla did was in a closed environment, the X has a massive amount of interior air volume, the 'clean' air inside the car will leak out and make it appear to 'clean' the air around it.
 
I read this whole thread but am still unclear about 2 things
1. Bioweapon defense mode cannot be "fan on max and recirc on", because to pressurize the cabin, you MUST get outside air into the cabin - more outside air has to come in than gets out (through leaks or through wherever the air comes out normally) to maintain positive pressure. If you turn on recirculate and if that means no fresh air at all, there is no way the pressure inside the cabin will increase. Read the blog post Putting the Tesla HEPA Filter and Bioweapon Defense Mode to the Test too. Bioweapon mode is cleaning the air outside the car too. So, does anyone know for a fact what exactly bioweapon defense mode does (no guessing)?
In my X on V9, when I crank to 10, it switches to recirc. When I turn on Bioweapon Defense Mode, it goes to 9 and recirc is disabled. I know previous comments indicate max fan elsewhere in this thread, and I may have previously commented that wasn't what I was seeing in V8, either, but I don't remember for sure.

Beyond that, see this tweet from Elon:
Elon Musk on Twitter
So maybe recirc would turn on automatically in certain circumstances even though it is usually disabled.
 
....and nor is the rest of the car air tight. The 'demo' Tesla did was in a closed environment, the X has a massive amount of interior air volume, the 'clean' air inside the car will leak out and make it appear to 'clean' the air around it.
The air has to be displaced to come out of the car. It is pulling outside air, cleaning it, and pumping it into the car, which forces the air in the car out (positive pressure). Eventually this means it's forcing clean air out as it continues to suck outside air in. His point was this is NOT recirc.
 
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I know air can get around the frunkbasket but it is a much less than ideal airpath than regular cars where the airflow is more "straight" in the direction of the car's travel. I asked because I was trying to get clues on whether the HEPA filter is in the fresh air intake path, or perhaps really more in the recirc path. Yes I get that around the frunk is not sealed in any way... Which makes it even harder to explain how cabin air could be recirculated through the HEPA filter without introducing fresh air intentionally or accidentally (into said HEPA filter).

I disagree with "high pressure goes into low pressure" as in this case I assume (ignoring the dampers for a moment) the motorized fan immediately behind the filter / filters has to run to create said pressure difference eg pull in the air across the filter, into the "inlet", whether or not the car is moving. If the cabin (other side of fan) is pressurized to a higher pressure than the outside (which must be the case for bioweapon defense mode to make sense) then said fan must work even harder to keep pulling air from low pressure to already-high pressure. Which is probably why it has to run on a high speed (apparently 9 or higher?).

So now a remaining question is - is the car, in bioweapon defense mode, also controlling the air flowing out of the cabin, by means of some dampers on the "outlets"? I assume that cars in general have air outlets to manage airflow in the cabin, they don't just pump air into the cabin hoping it will "leak" out of random door/window seals.

The point of all this is to speculate whether or not bioweapon defense mode = "temporarily turn fan speed up" and nothing else, e.g. worth $300 of software change in addition to $200 HEPA filter.

Here's a random article google found about airflow inside cabins. https://www.researchgate.net/public...fer_in_generic_passenger_car_mini-environment
 
I assume that cars in general have air outlets to manage airflow in the cabin, they don't just pump air into the cabin hoping it will "leak" out of random door/window seals.

You do realise we are talking about Tesla, the company that used glue which turns yellow in UV light for the main computer touch screen, taken 4 years post launch to designe motor mounts that don't vibrate on acceleration, installed windshields with double vision at night, used rubber strips that break down in heat, steering components that break down after less than 30k miles usage....I could go on.

Anyone who think the 'Bio defence' mode is anything more than a fancy graphics icon (not even that fancy) and a sub $80 market value HEPA filter hasn't owned a Tesla long enough.
 
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The HEPA filter is with zero doubt for fresh air intake, not recirc. One side of the filter is completely open to the area behind the frunk, with no ducting that could be feeding recirculated air back through the filter. The air also doesn't come in through the frunk, which has a water tight seal formed when the hood closes. It comes in through the various vents and openings that allow fresh air into the area that surrounds the frunk tub.

Bioweapon mode doesn't need to have anything to do with special with ducting, it just has to achieve positive pressure in the cabin by closing the air return and bringing air in faster than it can leak out through the door seals. That ensures that the only air entering the cabin is passing through HEPA filter and exhausting out the door seals. I suppose it could be simultaneously recirculating some of the cabin air as well through the cabin filter.
 
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Bioweapon mode doesn't need to have anything to do with special with ducting, it just has to achieve positive pressure in the cabin by closing the air return and bringing air in faster than it can leak out through the door seals.

So this would imply bioweapon mode has to close the air outlets, not just crank up the fan speed... meaning simply installing a HEPA filter will not get me the equivalent of bioweapon defense mode unless I pay tesla $500
 
So this would imply bioweapon mode has to close the air outlets, not just crank up the fan speed... meaning simply installing a HEPA filter will not get me the equivalent of bioweapon defense mode unless I pay tesla $500

That assumes that the act of swapping from recirc to outside air doesn't do exactly that, divert between the cabin air return and outside air. All we know is there doesn't appear to be anything in the parts catalogue that indicates a hardware difference between HEPA and non HEPA vehicles.
 
So this would imply bioweapon mode has to close the air outlets, not just crank up the fan speed... meaning simply installing a HEPA filter will not get me the equivalent of bioweapon defense mode unless I pay tesla $500
Nope, all the bio weapons button does is turn off recirculate and crank the fan to 11. The hepa filter is worth the money, but the software button is not.
 
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So this would imply bioweapon mode has to close the air outlets, not just crank up the fan speed... meaning simply installing a HEPA filter will not get me the equivalent of bioweapon defense mode unless I pay tesla $500

Don't confuse Tesla marketing term for a software button with actual ability to withstand biological warfare.

Its a big HEPA filter fitted pre cabin air filter nothing more, nothing less.
 
That assumes that the act of swapping from recirc to outside air doesn't do exactly that, divert between the cabin air return and outside air. All we know is there doesn't appear to be anything in the parts catalogue that indicates a hardware difference between HEPA and non HEPA vehicles.
"divert between the cabin air return and outside air" - I don't follow. Nobody yet has disagreed that recirculate means, cabin air outlets get diverted to cabin air inlets, and the fresh air inlet(s) get closed. Are you suggesting turning off recirc means the air outlets get closed? That seems unlikely.
 
OK here's a chickenscratch. Not to scale. Filters and fans not shown to avoid confusion.
Anyone who disagrees with this, comments are most welcome.
howdoesbiomodework.jpg
 
OK here's a chickenscratch. Not to scale. Filters and fans not shown to avoid confusion.
Anyone who disagrees with this, comments are most welcome.
View attachment 500614
Looks nice!
The left diagram and right diagram look correct, but the right diagram should have fan = 11.

So the hepafilter gets inserted where you have the word "in" just to clarify. As you said, you didn't include those to avoid confusion.

I had my front all disassembled and that is how the air flows. (Model S, but same for X)
 
I saw a nice video of a guy testing a few settings, bioweapon defense mode sets his fan speed to 9 (not 11). He confirms that with the HEPA filter, regardless of bioweapon mode on/off, A/C only, or even fan only (A/C off), the particulate filtration effect is the same (as long as you are NOT on recirc), which is expected since we know the HEPA filter is always in the path of incoming fresh air. Confirms also if you hear Tesla say "HEPA filter is not used unless bioweapon d.m is on", that's BS (as many people suspected).

So then the remaining difference (other than turning the fan speed up temporarily and disabling recirc) is somehow pressurizing the cabin which would prevent particles from coming in through other openings and leaks like in cleanrooms, especially if the window were slightly opened (presumably accidentally). But that doesn't seem like it would noticeably improve the cabin air quality beyond what the HEPA filter does, seems more like it would make sure unfiltered air does not come in at all. Like you would want during a bioattack or driving through truly hazardous air.


What's the Difference Between Positive and Negative Air Pressure Cleanrooms? - Angstrom Technology
 
So today I purchased the HEPA filter (1045566-00-H) for $220 plus tax and installed in in my 2016 AP1 MX (without bioweapon defense mode). I took some pictures if anyone is interested. Observations:
- turns out my MX already had a HEPA filter (1045566-00-D), to my surprise. Was super dirty though.
- installation took half hour or so (on my own), no biggie.
- The air inlet at /under the front bumper has dampers, when you turn on recirc, those close. Turn off recirc, they open. This surprised me because I and others thought that the air coming into the hepa filter (located behind the frunk basket) is just coming in randomly from the area around / underneath the frunk basket, which seems open to the ... road below.
- It seems the outlet air is somehow coming back all the way to the front of the car again, so perhaps recirculated air also goes through the HEPA filter? Would be weird
 
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So today I purchased the HEPA filter (1045566-00-H) for $220 plus tax and installed in in my 2016 AP1 MX (without bioweapon defense mode). I took some pictures if anyone is interested. Observations:
- turns out my MX already had a HEPA filter (1045566-00-D), to my surprise. Was super dirty though.
- installation took half hour or so (on my own), no biggie.
- The air inlet at /under the front bumper has dampers, when you turn on recirc, those close. Turn off recirc, they open. This surprised me because I and others thought that the air coming into the hepa filter (located behind the frunk basket) is just coming in randomly from the area around / underneath the frunk basket, which seems open to the ... road below.
- It seems the outlet air is somehow coming back all the way to the front of the car again, so perhaps recirculated air also goes through the HEPA filter? Would be weird

At some point when you get you car looked at, ask to have BWD turned on. I eventually got it turned on for free by a nice service manager. The techs are happy to do it if they get supervisor approval.

Regarding recirculation coming back in, I remember Elon saying during previous wildfire in CA that the model 3 filter was pretty good, out car in recirculation and it will filter in like 5 minutes. So maybe recirculated air could go through there? Or maybee those dampers just keep air going through the cabin filter?

Probably need to replace my HEPA filter soon. It's almost been 3 years. I have to replace the cabin filter too.
 
Cabin Filters on Right Hand Drive Vehicles. Are they still behind the glovebox which is on the Left? ie does tesla Just mirror everything behind the dash?

Also, I'm seeing supplies of these on Alibaba.com for $37-$46. The $37 one is "Activated carbon material" , and the $46 version is "anti PM 2.5 Material". Anyone know which is the HEPA?
 
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