Vapour coming from vents when using A/C

[Korruptor]

I had some vapour coming from my dash vents. I don't know if there's something wrong? Does anyone know anything about this?

I used my A/C for the first time this week.
Temperature was about 34deg C (~91deg F) with very high humidity.
Very heavy traffic.

We were in very heavy traffic that was stop and go, clutch 1st drive forward a few feet, clutch stop, etc... We more or less did that for an hour and only drove about 3 km's.

We noticed, after sitting around for ~30 mins, that there was vapour coming from the vents in the dash.
At first I thought it was burning clutch from clutching so much, but it didn't smell, and it wasn't acting like smoke.
It dissipated quickly; few inches from the vents it was not visible anymore.
It also seemed to come and go. If I would get a chance to rev the engine a bit and the a/c compressor came on or turned off (I don't recall which) the vapour seemed to stop briefly, and then start again after a few seconds.

I used the A/C again a couple days later, and there was no vapour. The temp, humidity, and traffic were also not as bad however.

Could this simply be some humidity in the air from the a/c compressor or something?

[Andrews Chalmers]

When you say vapour - do you mean humidity? Or smoke?

[Korruptor]

It looks like thin smoke, but it dissapates quickly as it travels farther from the vents.
It does not smell like anything though. if it was smoke I would assume it would have some sort of scent to it.

I said Vapour because I don't know how else to describe it

[Korruptor]

I asked a co-worker who is semi-knowledgable with cars.
He said that his old Toyota Camry did the same thing and it turned out to be a leak in his A/C system, and that the vapour was being blown through the interior vents.

Is this a possibility in my case?

[MSCOFF]

make sure that the tube that allows the condensation to drain is not clogged. there should be a small puddle of water under the front of the car after the AC has run for a while.

[Korruptor]

make sure that the tube that allows the condensation to drain is not clogged. there should be a small puddle of water under the front of the car after the AC has run for a while.

Thanks! I'll check for that today. It's supposed to be a scorcher with high humidity again, so I'll peek underneath when I go to pick up my wife at work.

[MSCOFF]

hopefully you will find the line clogged. the moisture won't escape from the coil area and possibly some is being blown into your vents. I had an old mazda (no AC) which would fog up when I turned the defrost on. a mouse had made a nest in the duct work. the nest got wet when it rained, and the moisture was blown into the car. good luck. post your findings.

[Korruptor]

I left the car and AC on when I arrived at my wife's work yesterday. It was indeed hot and humid. After a couple minutes there was a small puddle underneath the car so I guess that the line is not clogged.

However, yesterday when we used the AC in traffic just as before, we had NO vapour coming from the vents.
I wonder if maybe there was moisture in the vent pipes the first time and the AC had simply been blowing it through the system?

Whatever the vapour was, it has not yet made a re-appearance. Hopefully It was a one time event.

[williamk10]

When you open your freezer at home, that is the same vapour you see coming out of your vents. The cold AC air and the hot air inside the car is creating the vapour. My car has had it before when cold AC air hits the hot air inside the car, it goes away after a while.

Think of how you can see your breath on a cold winter day.

[Korruptor]

That makes complete sense to me william. Thanks for posting that, I'm not concerned in any way now.