RennlistTomE

With the AC 'Off' and the temp setting for the interior air at the lower possible setting, do you get noticeably heated air coming through the vents?
This is the Spyder. But please, GT4s weigh in as well.
At ~ 65ºF, city speeds, evening (no sun, no hot pavement) the vents are pushing air at maybe 80ºF. This at all fan speeds.
Even after running the AC, the vent air temp returns to substantially above ambient. Anybody else?
....yeah yeah I know...top down...turn the radio off...all of that. Got that. Still curious.
Thanks and Cheers!

iliveoncaffiene

With "A/C Off", your car cannot really make the air any cooler (compressor is off). The air doesn't magically appear from outside your car to inside your cabin - there's some internals it's going to pass through which are going to be warmer than ambient.
So, from a technical standpoint, this makes complete sense that without AC on the temperature dial will only affect 2 things: fan speed (in the case of AUTO mode), and how much to heat the air (in this case, not at all because the air is already warmer than you want).

TXshaggy

OP,

Been running my ac off down here in South Texas all winter. Yes, notice same. Anything above 60F ambient with sun out I go back to auto.

dnimi123

yes darn warm without a/c on

Westcoast

Hmmmm, I don't notice that at all, maybe you need to open the roof vent?

dnimi123

Ooooohhhhh the old roof vent in the cayman trick. I see....

Westcoast

Yep, the last time I remember cool or cold air coming into the cabin was when there were actual vents that channeled outside air into the car bypassing the HVAC system, either that or vent windows... sadly time marches on.

Then other observation I would make is that you are in Florida, if you come up north your experience will be a little different, the last time I was in California with a cab it seemed like the only way to stay cool when the sun was out was to turn on the AC.

But, with 65F air outside and no sun I would have thought that the air out of the vents would be cooler? I will take one for the team, head out tomorrow for a drive and compare the outside air temp to what comes out of the vent, please stand by!

Westcoast

RennlistTomE

Thanks guys for all of the helpful replies.
To clear up the apparent confusion in one post - 'some internals' don't necessarily warm the ambient air en route to the cabin. They might. Because of routing, or design, or improper set-up, or because the heater core shut-off doesn't work properly. This is the basis for the question.
Westcoast - Great! I'll be interested in your results. Have a great drive. My observations at ambient air temps in the mid 60ºF range: The vent air temp was consistently 80º-ish. So quite a change.
Cheers.

TXshaggy

Heading out; temps here low-mid 60s today. I’ll bring a digital gauge and measure...but your reports of 80’ish sound right from my past experience.

TXshaggy

Ok here we go with instrumented data.

TX Hill Country. Ambient temp 67F mostly sunny.

HVAC in manual full cold, ac off, max fan.

Start 67F measured with digital probe


After 30 minutes of moderate driving, same HVAC settings, 81F measured.

There ya go...this is why I go ac on above about 60F and top up.

RennlistTomE

Thanks Shaggy. I appreciate the precision!

Westcoast

Out here on the cooler west coast... AC off, manual setting of lowest temp 16.5C

11C mixed cloud and sun, digital probe in center vent started out within 1C of the outside temp (overnight car cold), fan set at 2 bars (low)

After 20 minutes the air coming out of the vent was 4.5C higher then the outdoor temperature
After 40 minutes the air coming out of the vent was 12c higher then the outdoor temperature
After 60 minutes the air coming out of the vent had stabilized at 16C higher then the ambient temperate, at this point 11C outside and the air from the vent was 27C (80.6F).

By this time the wife was giving me the eye, 'can we have some real heat?' she said, of course it is best to comply! Interestingly setting the temperature to 25.5C and the fan to Auto resulted in a peak temperature out of the vent hitting 68C! Eventually as the open cabin started to feed back some warmth to the onboard temperature sensor the vent air temp dropped to 50C and hovered around that for the rest of the road trip.

UncleDude

The commitment to science in this thread is impressive.

Black Adam

So the consensus is this is normal behavior. First time owning a Spyder. I, too, am experiencing this. Temperature is around 50's and inside the cab gets very warm feels like 80's. Btw, with AC off and top up.