Does your dual-zone HVAC do this? Need input
Thread Starter
Pro
Joined: Apr 2008
Posts: 628
Likes: 4
From: Columbia SC
Does your dual-zone HVAC do this? Need input
Guys, although I live in South Carolina I do not much like using A/C, preferring instead to run a "vent" setting bringing in outside air, windows up or down depending on how hot it is. When I try that in my newly-purchased 2003 coupe, the air coming through the vents is still slightly warm, even kinda hot down by my right leg. Could one or more of you dual-zone owners try this setting and see if warmish air is coming out of your vents too? I'd appreciate it. Perhaps the design is such that the 'vent' air is always warm and you have to turn on the A/C for cooling; I've read the service manual but it does not seem to address my situation.. Setting: A/C off, fan at two or three bars, ***** at full cool, airflow half-panel, half-floor. Thanks, Ralph Boineau in central South Carolina
Race Director
Joined: Jul 2004
Posts: 16,795
Likes: 62
From: Lake Havasu City, AZ
It is a common problem that many have experienced.
I believe it may be caused by a vacuum leak that prevents the vent actuators from properly operating or a problem with the indexing of the actuator or a fualty actuator Threre have been several DIY fixes posted for this in the past .
Have you checked the C5 tech tips section ?
Try searching on A/C actuator or A/C hot air
here is a link to one of the threads
http://forums.corvetteforum.com/show...ght=actuator+c
I believe it may be caused by a vacuum leak that prevents the vent actuators from properly operating or a problem with the indexing of the actuator or a fualty actuator Threre have been several DIY fixes posted for this in the past .
Have you checked the C5 tech tips section ?
Try searching on A/C actuator or A/C hot air
here is a link to one of the threads
http://forums.corvetteforum.com/show...ght=actuator+c
Last edited by rws.1; Aug 26, 2008 at 11:02 AM.
Thread Starter
Pro
Joined: Apr 2008
Posts: 628
Likes: 4
From: Columbia SC
Thanks, Richard
Richard, I appreciate your reply. I had searched posts such as you mentioned, but most if not all talk about actual A/C insufficiency. My A/C works fine, but turning it off and trying to just get outside air without warming is the problem. The 'vent' air is always at least slightly warm, even hot down by my right leg.
Drifting
Joined: Jan 2000
Posts: 1,660
Likes: 9
From: Charlotte, NC
I'm in Charlotte, and it seems if the exterior temp. is 75 degrees outside and you have the vent set to cool, the air it pumps in will be at least 80 degrees. I think this is because it is pulling in air from the engine bay which is quite warm.
In short, if you want cool air then you'll need to use the AC.
In short, if you want cool air then you'll need to use the AC.
Tech Contributor
Joined: Oct 1999
Posts: 41,037
Likes: 9,801
From: Charlotte, NC (formerly Endicott, NY)
There is a continous flow of Engine Coolant through the heater core. Even if the actuators are working properly the HVAC box still gets warm due to the proximity of hot coolant. If you can find enough room you could put a valve in the heater hose and control coolant flow that way but you would have to get out of the car on cold nights and reset the valve.
Bill
Bill
Drifting
Joined: May 2000
Posts: 1,917
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From: Southern NH
Ralph:
I have used my system in manual mode similar to as you describe and never noticed the air being hot, but I don't think you have a problem.
As you mentioned, to put the system in manual mode, you need to set the temp to full cool (60F). I also find I need to touch all other controls as well - fan speed, recirc OFF, and airflow vents and AC off. The difference is I usually set mine to dash vent only. Also, I only do this when the outside temp is in the lower 60s.
As Bill states, the heater core is always hot - no air flows through it when you set the system to cool but that cavity will still be very warm and may be the cause of the warm air you're feeling.
I have used my system in manual mode similar to as you describe and never noticed the air being hot, but I don't think you have a problem.
As you mentioned, to put the system in manual mode, you need to set the temp to full cool (60F). I also find I need to touch all other controls as well - fan speed, recirc OFF, and airflow vents and AC off. The difference is I usually set mine to dash vent only. Also, I only do this when the outside temp is in the lower 60s.
As Bill states, the heater core is always hot - no air flows through it when you set the system to cool but that cavity will still be very warm and may be the cause of the warm air you're feeling.
