heat/ac always "runs" even when "off"

[scdfndr]

Last week I bought a '98 SR5 6 cylinder as a second vehicle. I had it checked out by a top notch Toyota/Lexus only mechanic. I haven't driven it much and when I did I always had AC on because it's been warm here in SC. Today I turned the climate control system control to the "off" position all the way to the left. No air comes out of the vents. However I still hear the whir of the system as if it were running. It does this on all settings -- whether AC button is "off" or "on" and on all settings for vents: top, bottom, top and bottom. Also, the casing for the rear vent is broken and I can feel air coming out of it, which is either hot or cold depending upon the temperature setting. After reading other posts I checked and made sure the rear vent was in the "off" position. It is.

Any ideas? I'm not mechanically inclined and if this is a mechanical issue, I will take it in. I just want to make sure I'm not missing something obvious. I've driven only Toyota and Lexus cars all my life and know how the settings for HVAC work. So I don't think I simply don't understand what the settings mean, but I'm open to that possibility.

Thanks.

 

[Gerdo]

On the back side of the center console, there are heat controls. Also a fan control. This fan is under the passenger front seat. Is this fan turned on? The switch needs to be in the center position.

 

[scdfndr]

That was it. Man do I feel like an idiot. I read several posts where others encountered this same non-problem only to find out the rear vent was on. I checked several times making sure the sliding lever was "off." It was. I did not see the fan switch until just now. Many thanks.