White Dust Coming from Vents

fjroman2 · Thu Feb 05, 2015 2:54 pm

Hi all. This may be a really stupid question...but I have noticed some white particles coming from my air vents. I talked to the service guys about it and they said they had one other person complain about the same issue. They could not find a reason, but saw the white specks of (something), that was coming from my vents. I had them change my filter and went on my way...

In my opinion, it is almost like dried salt particles...not just normal dust. It is strange...and annoying since it really shows up on my charcoal interior. It seems to have died down with the filter change, but they showed me the old filter and I didn't really see anything on it that looked like what was coming into the car.

Has anyone else seen this? Thoughts on what it could be?

Thanks

fjroman2 · Tue Feb 10, 2015 7:29 pm

Man...it is strange that no one else is having this issue...why me?

Speed_Racer · Tue Feb 10, 2015 10:58 pm

Curious - where do you park your car (or what do you park under)?

Wed Feb 11, 2015 1:46 am

I first thought it was insulation or cabin air filter materials, but given it's salt-like, I'm thinking it may be the crystallized residue of fluids. You don't smell anti-freeze when you use the heater, do you? If not that, maybe some other fluid that may have gone through the filter or bypassed it. Did the new cabin air filter help stop the particles?

Sluggo · Wed Feb 11, 2015 2:18 am

This dust is not all that uncommon. A web search will show that many car forums have people with the same problem as yours. And the answer is... well no one has an answer that everyone believes.
But if you want to listen to what I have to say, well here goes... This dust is being made in your car. It is not coming from outside the car or the cabin air filter would stop it. Your A/C evaporator is the source of this white powder. The evaporator is made of tubes covered with aluminum fins. Now the white dust could be aluminum oxide, or aluminum rust, as the fins break down. Remember that these fins get wet, that's how the A/C removes the humidity from the air in the car. This is similar to the way distilled water is made and distilled water can be corrosive to metals, I don't want to get into that chemical process here, but it does happen. If this was happening don't think that the evap. fins would disappear. This corrosion happens very slowly and your evap. fins would last forever.
This is the reason the dust blows our when the fan starts blowing the fins on evap. coil have dried and the dust blows off. Once the evap coil fins get cold the moisture on the gets the dust wet and it will not blow off.

Ok, so now I'll sit back and wait for people to blow holes in my theory.

Wed Feb 11, 2015 7:28 am

I also think it's the evaporator coil, but possibly due to mold. Any funny smells? How often do you use AC? Do you air out the vents after using AC?

LPSISRL · Thu Feb 12, 2015 7:12 pm

I agree that it's not from the outside or the filter would trap it and it's not the filter itself. The aluminum oxide could be the problem but the question would be why wouldn't we all have that problem? Another possibility would be something that went down the vent or defroster, dried or decayed and is now coming out in. Does it come out the defrosters as well as the vents or just the vents? Maybe someone is messing with you and put some kind of powder or talc as a prank?

Thu Feb 12, 2015 8:41 pm

Sluggo wrote: Ok, so now I'll sit back and wait for people to blow holes in my theory.

Nope, I think you are spot on correct. My heat pump coils, inside air handler (same as inside car) and outside unit must be serviced and cleaned at least once a year to maintain the 10 year parts and labor warranty. Clean coils are more efficient and the system doesn't work as hard to heat/cool, so that's part of the warranty's requirement. They're sprayed down with water (or with a mild chemical cleaner if need be) and then rinsed as part of the annual service. Obviously, this can't easily be done to a cars heater core. So yeah, I'd easily buy in to your theory of self purging.

That, or, there's a very minor coolant leak on the inside core that evaporates quickly and eventually enough builds up and blows free. You see that white crud around radiators where they've been leaking slightly.

golftango · Thu Feb 12, 2015 9:28 pm

Kia makes a AC cleaner kit I'd recommend. Should be the same for the Suzuki. Find your evaporator drain tube and spray the contents of the cleaner up the tube. It expands and gets all the crud off the condenser/coils then drips back out the drain tube.

Here's a DIY video I did.

fjroman2 · Fri Feb 13, 2015 1:25 pm

Wow, thanks for the input guys. My A/C is almost always on...my car has the climate control system and it pretty much kicks on whenever I use defrost...and it doesn't automatically shut off. Quite honestly...the car stays pretty humid (even in the super cold), if it is not on. I am not sure what you mean by airing out the vents after using the A/C.

There is no smell. Definitely nothing like anti-freeze.
I park in my garage, pretty clean and dry.
No one is pranking me (that I know of).
I am still seeing it even after the filter was replace...but not as much.

Sluggo's theory seems like a very logical explanation...now...what do I do to stop it?

Is it because I have the A/C on a lot?