This seems almost to basic to post, but after actually reading my manual I still can't figure out how the ventilation system works! I've had a driver's license for 53 years and have driven too many cars to remember, but can't figure out how to use a fresh air ventilation system on this car! Gone is the simple knob or handle with AC, Vent, Heat, etc. on it! Read countless posts on how AC cuts down mileage On a warm day a few weeks ago I needed relief from the sun coming in the non-tinted windows (grrr!). Think I finally set the temp to LOW and adjusted the fan manually. Met another Prius driver in a parking lot and he said just set it on Auto and the temp you desire--this to me could turn on the AC--but does it? Members have really helped me on other questions--hope this doesn't seem too dumb!
Sorry, I deleted my original response because I became to uncertain of what I was trying to accomplish. Okay, let me try this... Try setting to Automatic (green light on) You don't set the temp to 'low' but to an actual temperature like '72'. Automatic will/should sense if the interior temperature is needs to be cooled down enough that it needs the AC or not. It will also sense the vents to use I think and what fan speed to use. Manually increasing the fan speed is possible but it will kick off Automatic and maybe the AC. I think the only time the desired interior temperature is displayed and settable is when you are using Automatic. There are parts of this system I am vague about too. I use Automatic, set the desired temp to 72 or 73, and leave everything else alone. I'm not certain if the AC will come on automatically when needed and go off automatically when not needed. It is a little peculiar.
To use the fan and without engaging the air conditioner. 1) Press the a/c button and make sure that the green light is off. If the light is illuminated the a/c compressor is active. 2) Press the recylce air button and also make sure the light is off. 4) Select the manual fan speed that you want. Do NOT use auto.
Thanks to both. Is the "recycle button" the one also called inside air? I know you need to have the outside air pushed--correct? I think I have used combinations of both suggestions! A related question: I know the AC will used up power (mileage) because of the compressor. Does running the fan (no heat) lower mileage?
IIRC correctly, most American cars have a VENT option on the climate control dial I don't think Japanese cars do. Some European cars to but I haven't seen any. (I've seen RES HEAT though for residual heat). If you're in AUTO and the A/C light is on, it doesn't mean the A/C compressor is running. AUTO means the car will determine whether A/C is needed so by having the A/C light on, the car will cycle the A/C as needed (or run it continuously if it's really hot). If you're NOT in AUTO mode, then yes, the A/C compressor is running. The A/C compressor is quite efficient (moreso in this than our 2005) so the mileage hit should be less. If you want just the fan, simply adjust the fan speed, adjust the mode, turn off A/C and bring in outside air. I find recirculating air makes it stuffy.
Yes but not as much as the compressor if it is cooling the incoming air. Think of your car as a closed system that is powered exclusively by the gas you put in the tank. Everything in the car that uses power decreases you mileage by some amount. The trick to knowing how much is in knowing what power is being drawn by the device being used. The compressor when actually compressing the refrigerant, uses lots more electricity than the fan alone.
I have a scangauge II with the AC power draw gauge. I can confirm that in auto the compressor cycles on and off. When it cycles on it draws about 250Watts. If you crank it all the way to LO then it draws 500Watts (with the fan on the highest setting.)
You are not alone in this issue. I also struggled with the air settings and finally came to the following . . . Set the Temp to 73 degrees Fans are set to face and feet The air conditioner or heat cuts in as it needs to; change the airflow to defrost as it's needed; change the fan speed setting to meet my needs; open my drivers side window when I wish; and that's it. Cheers!
