I live in Sacramento, CA. Dry air, temperature ranges from 40 to 110. Lately it has fluctuated between 60 to 92 over the last few weeks. When no one else is in the car (my wife and daughter cry for the A/C), I have the A/C set to Off, the 'fresh air' light is on, the temp set to 60, and the blower on the second level (2 led's lit). The display shows all the settings. I don't get cold air like if the A/C was turned on, but I don't get hot air either. I did notice when I first got the car that when the temp was set to 70 and the A/C was off, the air blew out warmer, whether the outside temp was 65 or 85. All I need is a fan to blow across my face and I'm fine, until the outside temp gets above 95. So the way I have it set has kept me comfortable. With the fan on and A/C off, I don't notice any loss of power like I do with the A/C on.

I also don't notice a difference in MPG with the system off or just the fan on with temp set to 60 (again, the A/C IS off). I get about 46mpg, mostly city driving, mostly short trips (4 to 15 miles). I only have 2300 miles on the car, so what I'm reading around here I should keep seeing that number improve as the car breaks in and I do the first oil change.