[DeanAnna]

We're wondering if anyone else has noticed this. Even if outside temp is 68 degrees, temp coming in through fresh air vents are above 80 degrees. Dealer service tech tells us this is typical of new GM vehicles, it's heat coming off the engine, and you need to have AC on. Doesn't seem an efficient design. Anyone found a solution?

 

[mjw930]

Been that way on almost every car I've owned over the last decade, GM, Ford, VW, Porsche, Jeep, Mazda, Volvo..... You just need to put the climate control on a temp, set it to auto and forget about it. The days of manually cycling the A/C to save gas or keep from robbing power are long gone unless you are competing. In everyday use you will never notice the difference so just set and forget.

 

[Boomer]

Been that way on almost every car I've owned over the last decade, GM, Ford, VW, Porsche, Jeep, Mazda, Volvo..... You just need to put the climate control on a temp, set it to auto and forget about it. The days of manually cycling the A/C to save gas or keep from robbing power are long gone unless you are competing. In everyday use you will never notice the difference so just set and forget.

Its not that way on my 2011 Cady CTS or my 2012 Cady SRX. If I set the temp at 60 (lowest possible) without having the compressor engaged (no AC on), it will vent close to (slightly above)the outside ambient air temp down to 60. If I set the temp above the outside temp, again without the compressor on, it will vent at the temp I have set. So when its cool outside I can vent the cool outside air on trips without having the AC or compressor engaged. Correspondingly, if its cold outside I can vent warm air without engaging the heater. DeanAnna should try setting the temp low as possible without the compressor engaged to see if the vented air goes below the 80 degrees. However, 68 degrees outside probably would not be cold enough to keep the inside temp comfortably low enough because of solar and other warmth entering the passenger area due to engine/trans etc. residual heat. This, of course, works better at highway speeds. But I haven't received my C7 yet and don't know if it functions differently.

Also I'm not in Florida or southern Cal. Here it is 30 degrees. If you "set it to auto and forget about it" won't the compressor engage each time as you start the car? I've heard thats not real good for the system. When I use my AC or heater I always turn it off before I turn the car off.

 

[ilsaair]

Am interested in your problem. First - leave it on auto and let the computer do the rest. Second - when you use AC do you still get hot air out if bottom vents?


Sent from my iPhone using Corvette Stingray Forum

 

[mjw930]

Dropping the temp to its lowest setting without having the AC on will cause the fan to run at close to Max speed as it tries to cool, the volume of air will counter the systems tendency heat the air above ambient as it passes through the engine compartment so you get closer to ambient. There is no way to turn off the heater so raising the temp to 80 will heat the air with the heater, period.

In a modern car there is no reason to turn off the AC when you stop the car. When you start the car the computer decides when to turn on the compressor when it's in auto or manual mode with the AC on.

Like I said before, set it on auto and use the temp setting to get the interior to the temp you desire and only worry about turning off the system when you are competing. It will cause no significant loss of fuel economy or hurt longevity.


Sent from my iPad using Corvette Stingray Forum

 

[BOBSZO6]

Ok, same here.
Its 60* outside and I get warm air from the vents with them set at LO on both driver and passenger sides.

The car is idling in my driveway for about 10-15 minutes when I took the photos; was driven about an hour earlier.

Here are the air settings and the temperature from the mid vent:

106*


This is the way it is? Are you kidding? @#$%^&


Must be a recirc. problem with the vent system not getting outside air OR the Heater is FULL ON.

*** Is there a fuse I can pull to disable the heater?******
I don't have a schematic of the electrical...ANYONE?

Q... If I just want to blow cold outside air thru the vents it is NOT possible?

 

[Z06 Owned]

Just a thought...fresh air comes from the cowl area, right? The Z's underwood temps get crazy hot very quickly. Pulling hot air from the cowl area would cause that reading, no?

It was 82 degrees the other day. My outside temp reading was 124 degrees. I'm told this is possibly due to the Novi-bra. But, it shows how hot the air gets around the engine. Not much air passes through that engine bay.

I've found that unless I run the AC, air coming thru those vents is pretty hot once the engine warms (unless it is pretty cold outside).

 

[BOBSZO6]

With the air set to "LO" there should be 100% outside air entering thru the vents. With outside air at 60* it should be very cool air entering via the vents.
No air inlet location is going to heat the outside air to 106*F without a lot of help.
The heater must be on FULL to get to that kind of temp from the vents.

I note that many are seeing this same issue.

HELP!!!!
I'm baking in my new Z06

 

[53Vette]

If I read this right, you don't want the aircon on just fresh air keeping you cool? I'd first take it to the dealer. Have them look into it. But I'd also just turn on the aircon.
The air coming through the vents will be cooler when the car is moving. Even in my transport truck it cools off when I start to move.

 

[Busa Dave]

This is a well known issue... It is even worse in stop and go traffic but mine even with a ambient at 68-70 have to turn everything off and roll down the windows unless you want to run the ac. Not all cars are this way but many of them are. My 2013 Jeep does it but my 2014 Sierra Denali does not.

Might also remove the cover in the middle of the grill that has corvette written on it and the mounting behind it--takes 3 minutes with a Phillips screwdriver and instructions in the manual more cool air is better.

 

[meyerweb]

I've seen similar on some other late model cars. It seems the coolant flow is such that it ALWAYS flows through the heat exchanger, even with the temp set all the way down. I don't know if this is true of the Stingray, but it's likely. The heater box should have a door of some sort that opens / closes to vary the amount of heated air that mixes with the cool(er) outside air. If that door is not closing properly, it could cause the problem you're having.

OTOH, it may be that the system never completely shuts off the flow of heated air, by design. Since most people run the air conditioning all the time, Chevy could have decided it didn't matter. That seems unlikely, though, as it would make the A/C run more, which would use more fuel. But you could bypass the heater core during the summer by disconnect the hoses that attach to it and plugging a short piece of pipe between them. But you'll have no heat on those occasional chilly mornings, and defrost might not be very effective on really humid days.

On the Miata forum, someone mounted a valve and a couple of fittings such that with the valve in one position, water flowed through the heater core, and with it in the other it bypassed the heater and just flowed backed into the cooling system. Something similar should be possible on the Stingray, if the hoses are relatively accessible. Use an electrically activated valve, and you could even control it from inside the car.

Here's the thread from the Miata forum. Start at post # 57. http://forum.miata.net/vb/showthread.php?t=375731&page=3

I'd start by having the dealer make sure the heater airflow door is working properly.

 

[BOBSZO6]

^^^

I think you are correct on the damper door not working properly!

Someone else said this: "Sounds like the air blend door between the evaporator and heater core is not opening and closing correctly. Could have gotten something stuck in there. My 08 when is set on 60 degrees with no ac blows as cool as outside temp."

Bingo!!!!

Failed damper door actuator...

 

[mjw930]

Take it out of "Auto" and select the dash vents and see if that changes the air flow.

 

[BOBSZO6]

Take it out of "Auto" and select the dash vents and see if that changes the air flow.

Definitely the damper door is stuck. I will try cycling from hot to cold air and see if I can get it to move.
I have tried all vents and just with the lower vent I do get cool air!
But with the upper vents....it is HOT! Like I said with the heater on Full.

 

[Derbo2]

Mine is the same as yours Bob. I've tried cycling through each heating and cooling mode and I can't get ambient temp air to enter through the vents. I'd be a happier guy if a solution could be found.

Derik

 

[mjw930]

Kind of sad a 2015 is having this problem as there was supposed to be a software fix in 2014 to address this very issue. Sounds like you may have a physical component failure, sounds like a dealer visit.

 

[BOBSZO6]

Mine is the same as yours Bob. I've tried cycling through each heating and cooling mode and I can't get ambient temp air to enter through the vents. I'd be a happier guy if a solution could be found.

Derik

I have seen many responses on other Corvette forums that is the case.
Seems to be a design issue during installation something gets torqued too tight and the door won't open/close properly.
I'll be taking it to the dealer after some more miles. Only have 80 miles on a new Z06.

 

[Busa Dave]

My build date was 2-10 if it were a manufacturing process issue it would stand to reason that the systemic cause would have been isolated and remedied. I hope it is a blend door actuator. My raptor went through 3 in 2 years lol.

 

[dwward]

Interesting. I'll have to see if I can recreate this issue. All my cars are on 'auto' all the time, even when the top is down.

 

[Derbo2]

I'm not sure where the intake for the ventilation system is, but if it is anywhere under the hood, then hot air is all we can expect. The hood seems to really trap engine heat without venting it out thoroughly. This is the only car I've owned where I've needed to use air conditioning when its 65 degrees outside. I drove a Viper once and it nearly melted my shoes to the pedals.......I guess with lots of power comes lots of heat. I can live with it, but would love to hear of a fix.

Derik