On Saturday (9/1), I began to notice quite a bit of visible condensation "mist" coming from my A/C vents (almost like a very faint white smoke). I know this can happen in really humid environments, but I have never seen this prior to this past weekend. It also doesn't seem to be quite as cool as it should be (or I am used to). I keep my A/C on Auto and have the temp set anywhere between 69 and 71 degrees. I live in Tampa, FL, but this past weekend was no more hot and no more humid than the last 100+ days. There is no smell associated with the A/C running. Again, this just started to happen; A/C operation was fine prior to this.

I have read that a plugged up drain tube could be to blame. I haven't really gotten under the car to see if there is the normal amount of water from the condenser under there. Could this be a possibility? If so, any ideas where the drain tube is exactly (I again read that it is against the firewall on the passenger side of the engine compartment - can anyone confirm)?

Perhaps it just needs a recharge? FWIW, my '05 A/T has just over 51,000 miles.

Thanks!

 

I'd say that the "mist" is a normal occurrence on very hot humid days as water vapor will sometimes exit your cars vents when hot humid air passes through the A/C system too fast for the condensing moisture to form into water droplets.
No need to crawl under the car to see the drain, look for water, puddle, under the car in the middle after stopping. Usually if the A/C is on recirculate, this will help the situation.

 

There is some water under the car after running the A/C. However, the air is definitely not as cold as what it used to be. It also seems to be more humid (not a cold, dry air). Also, when starting the car, it sounds like a hollow, suction noise emanating from the ducts/under the dash as the A/C kicks in. These are all things that just started within the last week or so.

I'm taking it to an A/C shop at the end of this week. I'll get a quote and what they think might be the problem. Hopefully it's nothing serious.

BTW... what do most of you think about getting work done at an independent ASE certified A/C shop versus going to the dealer?

 

In for updates.

 

Filter changed recently?

 

Not recently - I meant to do it a couple of months ago, but the auto parts store I frequent was out of stock. I'm about 11,000 miles past due to change (I think they recommend changing at 40,000 miles, right?)

 

I changed my cabin filter about 6 weeks ago and had the mist this past Saturday (very very humid here) , so I'm going to say that's not it. I'm guessing it may be the compressor cycling on and off and the mist shows itself while the compressor is in the off cycle - not dehumidifying.

 

Well, in preparation for taking the car into the A/C shop tomorrow, I thought I'd go ahead and replace the cabin air filter myself.

I got the car when it had just over 19,000 miles on it (back in 1/2008). It now has 51,500 miles on it (9/2012). I bought it from my father-in-law, who was meticulous in keeping up with the car (via the dealership). However, I have no way of knowing if it was ever changed (I could probably call him, but I doubt he would remember). One of the tabs that holds the cabin air filter frame into the housing was bent way back, so it was either like that from the factory or it happened during routine service. Anyway, it is probably safe to assume that the old filter had at least 30,000 miles on it. And here is what it looked like (compared to the new one (which is just a Puralator))...



Oops.

I didn't notice any difference in the A/C after I changed it (wasn't really expecting it either). I didn't remount the glove box either, in case the A/C shop needs to get in there (I'd rather not have them yanking on that thing like I had to do).

I'll post back either later this weekend or first thing next week with what happened at the A/C shop. Wish me luck.

 

May be low on R-134, causing the evaporater to ice up, then fan blows some water vapor out the vents.

 

I'm hoping that is it just low on refrigerant. I always thought these systems were completely closed systems, and that the refrigerant will only go low if there is a "non-natural" leak. But a little online investigation has proved me wrong...

I think that when I take it, I'll ask them to check the refrigerant level first before doing anything else. Assuming a 10% lose per year, and the car is an '05, then that means I have about 25% to 30% refrigerant left. When I was in there last week explaining the problem and setting up the appointment, they suggested they would put in the UV dye and then inspect it 30 to 40 minutes later. I guess this can't hurt. I just saw another site (an A/C shop) recommend getting the A/C purged and refilled every 3 to 4 years as a preventative measure (due to the lubricating oil contained within the refrigerant).

 

On a 90+ degree day an A/C will not perform as much as normal.

The fact that you had condensation tells me the inside of your car was hot and the vents were cold.

Good call on that filter. It was a tad over due.

 

Over the last week, the A/C has become much less effective; it barely blows cool, even on recirculate and while moving. It was a pretty dramatic drop in effectiveness since 9/1's "white mist" event.

Anyway, I'll know more tomorrow. Thanks for all the replies.

 

Well, I won't know tomorrow. Too much stuff going on tomorrow to the point where we (family) can't be down to one vehicle. I am rescheduling for Thursday, 9/20. Ugh.

 

Be sure to post back when and if you get something from the dealer.

 

a dirty filter can cause more condensation than normal if there is not enough air passing over the coils... same thing happens on any a/c system...

 

I got the car into the shop (Ice Cold Air) this past Thursday (9/20/12). Initial tests of the A/C found very low refrigerant and a lot of air in the system. They went ahead and evacuated the system, then refilled the refrigerant and oil and added a dye. About an hour later they called and said the evaporator core is leaking pretty bad. I got a run down of the prices for the parts, and then quickly checked some of our vendors' prices to see if they were in line. For the most part they were (a little higher), but considering I had gone just over two weeks with no A/C in Tampa, Fl, I went ahead and told them to make the fix. $697.67 later, I had cold A/C again. Here is how the parts broke down...

Expansion valve - 74.91 (no labor as it is close to the evaporator core)
Evaporator core - 189.87 (labor at 3 hours - 195.00)
O-Ring - 8.75 (no labor)
Oil - 13.85 (no labor)
Refrigerant (x2) - 44.90
Evacuate & Recharge - no material cost, only labor - 89.99

Supply charge (boo) - 34.76
Tax - 45.64

All parts come with a 12 month / 12,000 mile warranty on parts failure and a 90 day warranty on labor.

So, hopefully I am good for now. BTW... I asked what the general life expectancy is on an evaporator core these days; the service manager said about 7 to 10 years. Seems a little short to me these days. He stated that while the A/C is not running, the evaporator core actually holds a pretty good amount of refrigerant and lubricating oil. The two apparently create a rather acidic mix that can corrode the evaporator core from the inside out. Anyone intimately familiar with auto A/C systems buy this?

$700.00 is a little hard to swallow. I have to remind myself though that $700.00 is roughly two car payments these days (for an average sedan no less). I'd rather pay this than be paying car payments every month for several years.

Thanks everyone for your posts.

 

Sorry about having to shell out $700, but as you mentioned - in FL it's a must.

Thanks for posting your outcome.

 

Just thought I'd reply as we're in Florida now for a month of needed vacation time and the A/C is running full blast.
Evaps will rot from the outside as any debris that may enter the HVAC air intake system, takes up residence around the evap and the continued moisture held by the debis will attack and rot the evap. Jeeps, to use as an example, were known to have the evaps rot in 2-4 years as Chrysler made the evaps with very thin metal to aide in cooling, but because of this engineering wonder, they rotted out quickly especially in hot humid climates with the great amount of moisture being removed and water continuously on the evap.

Also to add, the factory systems are like a refrigerator, freezer, home A/C unit, as they should not loose any refrigerant unless there is a problem, and the refrigerant and oil combo causing an acidic mixture to cause the problem is, at least to me rediculous, but regardless, it's fixed and you can stay cool.