Air Conditioner/Heater Auto Mode-Manual ?

[dorf]

2007 model----Outside air temp about 30F.
Air/Climate/Heater in Auto. I tried to turn off the Air but the dash display still showed AirCondOn.Even with the MFD showing off.
I finally discovered if you turn off Auto,. Select Temp and Fan and speed the dash display goes away.
I usually drive with the sys in Auto and drive on.
Today the mileage was going down hill, about 29 at the lowest.
After re-setting all to Manual, the mileage is back up to 47.3 or so. Amazing !!!
Evidently the air conditioner compressor runs continually while in Auto mode.(wether it is needed or not)
The Prius manual is pretty vague in this respect.
What am I missing.????

[V8Cobrakid]

i know what you're missing....

there are about a dozen other threads on this.. and somehow you missed them

auto a/c mean auto air conditioning.. it doesn't not mean air conditioning. by auto it regulates the temp and humidity levels of the car and keeps it sot he car stays a comfortable temperature.

if you set it to 72.. it will warm till it hits 72.. then it will slow down a bit.. and if humidity gets too high, it will kick on the consensor to lower humidity and then shut it back off again.


set it and forget it.. much like the rest of the car.. oh yeah.. please do a google search under priuschat for Auto AC or automatic air conditioning.

[dorf]

I got it....and also by auto it means the your mileage is automatically going down. 29 to 47 is BIG

Seems like "Manual" way is only the way to go.

Comments anyone ????

[seasalsa]

Originally Posted by dorf

I got it....and also by auto it means the your mileage is automatically going down. 29 to 47 is BIG

Seems like "Manual" way is only the way to go.

Comments anyone ????

Yes, it is not the compressor. Probably the driving conditions and or outside tempersture were the major factors contibuting to the MPG.

"Today the mileage was going down hill, about 29 at the lowest." Sounds normal for 1st 5 minutes at 30 degree temperature.

"After re-setting all to Manual, the mileage is back up to 47.3 or so." Aoto/AC would probably have had the same results after the ICE was warmed up.

Like the Kid said just set it and forget it.

[KTPhil]

Originally Posted by dorf

Evidently the air conditioner compressor runs continually while in Auto mode.(wether it is needed or not)

Not true. The yellow bar above the a/c button only means that running the a/c compressor MAY be used if required, NOT that it is actually running the compressor at that moment.

Also, the compressor is variable speed, so even when it IS running it may be using very little energy if cooling requirements are moderate.