Dual Climate HVAC issue or normal?

[jbangoy]

When I don't have the AC or Heater on, I always feel air coming from the vents. Doesn't matter if I had the air set to fresh air or recirculate, there is always air coming through the vents. I push off and I hear the fan blower stop, but if I had the temp set to a low temp and the AC was on I still feel cold air coming in. If I had the heater on I still feel hot air coming in. On days I just want to open the windows I still feel air blowing that is not the ambient temperature and can't figure out if this is normal. The only way I have found to get ambient air is to turn the dial down to 65, manually turn off the AC button, and then press off. This works, but it is still annoying as every other car I have had OFF means off. No air goes through the vents. I do not use the Auto function at all.

[SpecBlitzed]

Yep the Auto HVAC has a mind of its own. I noticed it a lot when I first got my car. I have learned to deal with it and set my temp. to close to the same as my outside air temp.

[lgt_nube]

Get ready for other annoyances. There's at least one very long thread here about the annoyances of the HVAC and how to deal with them.

 

it is still annoying

[iNVAR]

When you press off, everything shuts off, and the vents automatically go into "fresh air" mode, which means that if you're at highway speed, the force of air pushing against your intake-vents will make air come out your inside vents.

 

If you want to shut that off, then press "Off" and then hit the recirculate button. No more air coming from the outside.

 

If it is freezing cold out, and you had your heat on set to 75, and then you hit off, the following will happen:

• your vents will go to 'fresh air' mode
  
• your heat core will still be warm and heat will still come in, if your car is moving fast enough to push air through the vents
  

 

If you want to shut everything off completely and just want fresh air coming from the outside, first turn the temperature knobs down on both sides to the lowest (65). Then press off. Then press the fresh air button. Air coming from the outside then should neither be heated nor cooled. If you want NOTHING to happen at all (no air from outside), then hit recirculate.

 

I find a good effect to have on a nice cool day when you don't need the AC but want some fresh air but don't want wind noise from windows is to turn it down to 65, press off, hit fresh air, then crack open the roof. This makes for a nice cool breeze coming from your vents which gets evacuated through your roof.

 

You just have to remember this when messing with the climate control: when you press auto, the computer attempts to reach the temperature you set most efficiently and most quickly by manipulating ALL of the controls available to it.

 

When you press a button, it takes that particular item out of the computer's control. The computer then tries to manipulate other controls around it. And if you take another, it works on another, etc. So if you set it full auto at 70 and it's hot outside, it'll do its best to get you to 70. But if you only activate the footwell vents, it may decide to raise the fan speed to pump the cold air out, etc.

 

Another interesting thing to note: when you start your car in the winter and it's freezing and you have it on full auto, it keeps the fan on the lowest speed setting and on recirculate until your car warms up to the first line on the gauge. Then it starts pumping hot air out the footwells. It does the footwells because heat RISES naturally so by pushing air down there, it quickly circulates the air in the cabin. Whether you like it that way or not is up to you.

[jbangoy]

So OFF and then recirc "should" turn everything off? Will try and if not I'll just deal with it...

[iNVAR]

Turn temp knob to 65 on both sides, press off, then recirculate. That should effectively take your climate control out of service and it should remember it even if the car is shut off.

 

If you don't turn the knob down, I believe the heater core still gets hot coolant which can affect the temperature in the cabin, but not that badly since you have the vents on recirculate. I'm not sure why "off" doesn't automatically switch air to recirculate mode... maybe a safety feature to make sure occupants have fresh air. I dunno.

[ssbtech]

I remembered this thread while driving tonight.

 

My A/C was on recirc when I turned the whole system off. No air flow through the vents when I was stopped. As I started driving, air could be felt. There's a cabin vent down by the rear bumper (on the wagon, not sure about the sedan) and I'm guessing what is happening is that driving causes low pressure outside this vent and, combined with higher pressure at the HVAC intake, causes air to be drawn through the dash vents.

[jbangoy]

Turn temp knob to 65 on both sides, press off, then recirculate. That should effectively take your climate control out of service and it should remember it even if the car is shut off.

 

If you don't turn the knob down, I believe the heater core still gets hot coolant which can affect the temperature in the cabin, but not that badly since you have the vents on recirculate. I'm not sure why "off" doesn't automatically switch air to recirculate mode... maybe a safety feature to make sure occupants have fresh air. I dunno.

 

This works to shut off for me thanks