Why is cold air coming out pillar vent even with heat on?
11-24-2007, 03:42 PM
#1
Member
Thread Starter
Join Date: Oct 2004
Posts: 105
Likes: 0
Received 0 Likes
on
0 Posts
Why is cold air coming out pillar vent even with heat on?
I had my heat on today. In terms of vent distribution I have it set to auto. Warm air is coming out of all the vents except the rear pillar vents on the side of the car. Freezing cold air was coming out. I'm a new A6 owner, can someone tell what I'm doing wrong??
11-25-2007, 12:03 PM
#4
AudiWorld Senior Member
Join Date: Jun 2000
Posts: 799
Likes: 0
Received 0 Likes
on
0 Posts
Any air flow over the glass would reduce fogging
even if it was "cold" relatively speaking. Maybe the channel is so long that it takes a while to warm up? I'll have to check mine in the morning.
11-25-2007, 12:29 PM
#5
AudiWorld Super User
When you hit the defroster, the A/C compressor kicks in to dry out & cool the air...
With cool, dry hiting the windshield, it will pick up the mositure and defog the glass. A little heat added to the dry air facilitates the defogging as it vaporizers the moisture on the glass and allows the dry air to pick it up, recirculate it to the evaporator where any moisture condenses, and then drains out of the cabin.
11-25-2007, 08:22 PM
#6
AudiWorld Super User
Not quite true
True, the compressor kicks in, to reduce humidity - but at the same time the heater does its best to heat the air as quickly as possible AFTER it came thru the evaporator (after the cooling), because warm air can contain more humidity than cold air, before condensing.
Also, at temperatures below +5C - ish, the compressor (and thus the cooling) won't run at all, because of ice formation, which would be very bad news. See manual on that topic.
So when you hit the defroster button, initially you will indeed get freezing air, but as soon as the engine warms up you'll get warm air, as warm as the engine and your pre-set temperature allows. Because the OP said that warm air is coming from other vents, I must assume that the engine is warm, and that the temp setting isn't set on LO (lowest possible). Even the lowest automatic temperature (I believe it's 65F) is typically warmer than the outside air at a time that you're experiencing condensation (winter).
I am from Switzerland, so I know cold weather and what to do against it (and what the car does against it
)
Also, at temperatures below +5C - ish, the compressor (and thus the cooling) won't run at all, because of ice formation, which would be very bad news. See manual on that topic.
So when you hit the defroster button, initially you will indeed get freezing air, but as soon as the engine warms up you'll get warm air, as warm as the engine and your pre-set temperature allows. Because the OP said that warm air is coming from other vents, I must assume that the engine is warm, and that the temp setting isn't set on LO (lowest possible). Even the lowest automatic temperature (I believe it's 65F) is typically warmer than the outside air at a time that you're experiencing condensation (winter).
I am from Switzerland, so I know cold weather and what to do against it (and what the car does against it
)
Trending Topics
11-26-2007, 12:10 PM
#9
AudiWorld Member
Join Date: Oct 2005
Posts: 489
Likes: 0
Received 0 Likes
on
0 Posts
Unless the ECON light is on, the A/C is on all the time. Temperature
is adjusted by the air mix door allowing the correct proportion of cold air (A/C) and hot air (heater core) to come through.
But it's wierd. Sometimes I even get hot air blowing out from the side vents (but ice-cold air from the center and rear vents) on a hot summer day even when the A/C is on full.
But it's wierd. Sometimes I even get hot air blowing out from the side vents (but ice-cold air from the center and rear vents) on a hot summer day even when the A/C is on full.
11-26-2007, 01:40 PM
#10
Cat Herder
mine did the same thing on the way home...68F on ECON, 43F outside. heat everywhere but.
maybe a software bug? I wonder what the '08 A6 MMI versions are shipping at...