Dual Climate Control Heating Question..
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,100
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From: Massapequa Park, NY [This is Not an EXIT]
Dual Climate Control Heating Question..
Since this is my first winter with my Vette I just started using the heat. WHen I hit the Auto button (or any mode) The AC light always comes on even when hot Air is coming out.
I know my AC works fine, and it seems like the heat does too. I was just wondering if this is normal to always have the AC light on. The Manual doesnt say anything about it.
I know my AC works fine, and it seems like the heat does too. I was just wondering if this is normal to always have the AC light on. The Manual doesnt say anything about it.
Pro
Joined: Sep 2003
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From: Lantana, TX
I hate to admit how much this bugs me too. Sad how I'm such a twit that I'd almost rather keep it off rather than 'heat' the car with A/C on sometimes. Just hate to think of anything robbing me of those precious horses when it doesn't seem that it needs to be on.
Anyone know why the A/C would come on when it's 50 outside and I have the temp set to say 75 inside?
Anyone know why the A/C would come on when it's 50 outside and I have the temp set to say 75 inside?
Race Director
Joined: Jun 2000
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From: Hurst, TX USA
I think if you turn it off you will start getting condensation on the windows pretty quick. Its only on to dry out the air. I think the manual mentions this in detail, but its been a long time since I actually read the manual. 
Advanced
Joined: Jun 2004
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From: MD
When I select auto mode when it is cool/cold the mode that is selected 10 times out of 10 is combo heat and defrost. This is what kicks on the AC. I know I've seen other posts, with better explanations, on this forum too.
Team Owner
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From: All that glitters is Gold - Hockey Is CANADA'S game
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St. Jude Donor '05-'06
GM uses the AC to remove the moisture from the air so when you defrost the front window the AC automatically comes on and cannot be turned off. The AC will not come one it the outside temp is below about 38F degree. This is explained in the owner manual. 
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Mine does the same thing. As far as I can tell, it is supposed to do this.
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From: Redsox, Pats, Celts & Bruins !!! Redsox Nation !!!
St. Jude Donor '06-'07-'08-'09-'10-'11-'12
Originally Posted by Villian C5
Ok at least I'm not the only one
Drifting
Joined: Nov 2004
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From: Lee's Summit MO
I belive that I have also heard that the seals are less likely to leak on the AC if it runs periodicly rather that sitting idle for months.
I have no resource on this though, so it may just be a wives tale?
I have no resource on this though, so it may just be a wives tale?
Instructor
Joined: Aug 2001
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From: Washington DC
Why does the outside air button always kick on and it won't let you turn it off as well?
I don't understand the logic of trying to heat 50 degree air to 80 degrees when you could just re-circulate the air that's already been warmed up.
I don't understand the logic of trying to heat 50 degree air to 80 degrees when you could just re-circulate the air that's already been warmed up.
Le Mans Master
Joined: Sep 2004
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From: Madison (Huntsville) Alabama
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St. Jude Donor '09
You need outside air for the defroster to remove the moisture sufficiently. I found that out several years ago when I was trying to remove condensation during a cold rain with the defroster. Turning it on only made it worse with recirculated air. I discovered that using outside air cleared the problem immediately.
They're being a bit too restrictive, in my opinion, when you have it set on manual. Doing all that is fine in Auto, but not Manual.
My Mazda truck also does this and it doesn't have automatic AC. The only place were the compressor is not on is with the panel vents; switch to floor vents for the heater and the AC comes on.
They're being a bit too restrictive, in my opinion, when you have it set on manual. Doing all that is fine in Auto, but not Manual.
My Mazda truck also does this and it doesn't have automatic AC. The only place were the compressor is not on is with the panel vents; switch to floor vents for the heater and the AC comes on.
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12
Besides as someone just mentioned, keep the compressor running keeps the system lubed. AC Coolant has red oil in it to lube the sysytem up. Some Car companies like BMW tell you run your ac at least once a month in the winter. Thats why most cars now, the AC always come on and you have to turn it off. My wifes Trailblazer does the same thing.
Burning Brakes
Joined: Mar 2003
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From: Arlington VA
Informative post. I understand why the AC comes on to dry the air and keep the moisture down inside the cabin. My biggest gripe is the fact that I cannot seem to override the AC by hitting the button to turn it off. This usually happens in AUTO mode. I hit the AC button and it blinks a few times, readout says SET AUTO and then the AC light stays on. Nothing in the manual about this issue that I could find. Maybe AUTO has the system is in defrost mode. I will try changing the mode next time and then turning off the AC. Any comments are appreciated. I like the HVAC controls on my Acura TL much better. Seems like I am more in control in that car.
Le Mans Master
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From: Madison (Huntsville) Alabama
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St. Jude Donor '09
Originally Posted by jcs712
Informative post. I understand why the AC comes on to dry the air and keep the moisture down inside the cabin. My biggest gripe is the fact that I cannot seem to override the AC by hitting the button to turn it off. This usually happens in AUTO mode. I hit the AC button and it blinks a few times, readout says SET AUTO and then the AC light stays on. Nothing in the manual about this issue that I could find. Maybe AUTO has the system is in defrost mode. I will try changing the mode next time and then turning off the AC. Any comments are appreciated. I like the HVAC controls on my Acura TL much better. Seems like I am more in control in that car.
Mine does the same thing even when it's not in Auto. I assume that's 'normal' (but not particularly desirable as far as I'm concerned).
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From: After reading this thread, I gotta tell ya... you're an ass. .
St. Jude Donor '05-'06-'07-'08-'09-'10-11-'12-'13
My display does not work, so I'm running blind. 
I bought the car 2 month ago with the display out. My AC light comes on as soon as I turn on the fan, then I hit the AC button twice and then it goes out.
I bought the car 2 month ago with the display out. My AC light comes on as soon as I turn on the fan, then I hit the AC button twice and then it goes out.
Instructor
Joined: Jun 2003
Posts: 155
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From: Magnolia DE
Select "Mode" until the arrow points to just feet. Press the "outside air button if it's not already selected. Adjust temp desired. Manual mode operation. If you have memory option, press mem button to save setting. It'll stay there until you change it.
