I have noticed in my 2009 Honda Accord that the temperature of the heated air coming out of the dash vents drops when I select “all dash” as opposed to “mix dash and floor.” It’s significant enough to notice as it blows on my hands. But the dealer says the difference is within 5 degrees, which is within specs, so they won’t do anything.
I don’t think I can measure it myself since I can’t fully jam my thermometer in the dash vent, so any reading would be contaminated by ambient temperature.
Is it possible that the slower air speed at the dash is allowing the whole air plenum to get warmer, and with a slower air, even the same temperature will feel different at different speeds.
That’s the entire theory of having a ceiling fan in your house. Moving air “feels” cooler…the faster it’s moving, the cooler it feels - regardles of the actual temperature.
If your car is like mine, “all dash” is actually the defroster setting. I can’t set mine on that setting without the AC coming on in the background to remove moisture.
Overall I love me car, but that’s a quirk that I’ve always hated.
Chaissos: My phenomenon occurs independent of fan speed. The temp changes with the switch between [face] and [face/feet]. I don’ t believe the change in volume of air coming out the dash vents matters since I don’t notice this temp change at the floor vents.
Mtn Bike: By “all dash”, I’m referring to the setting where most of the air comes out of the dash vents (picture with arrow to face).