I'm asking because today I figured I'd do a little experiment (a comfortable one at that): I left the HVAC in auto at 73F for my entire 15 mile commute in to work this morning.
What I observed doesn't fit with other observations. In my case the climate consumed 5+kW for a few minutes (after doing a precondition to 72F) and then the climate consumption dropped to the 1.5kW - 2.0 kW range and stayed there for the rest of the commute. (It was 45F outside so the incoming air had to be heated.) There is no way the car ran the A/C for the rest of the commute to cool the air.
If your observations are simply due to the power consumption level (during the summer the A/C by itself seems to consume the same 1.5kW - 2.0kW). Is it also the fact that you've felt cool air coming out of the upper vents? (In my case I did notice cool air coming from the upper vents but warm air was also coming from the lower vents.)
I can think of a few reasons for the power consumption:
- - Perhaps it *is* using the A/C like a heat pump in a reverse cycle
- There are two heating elements in the car, perhaps once its up to temp it only uses one
- Perhaps it can modulate the use of the heating elements (maybe they aren't a full on or full off)