AC compressor on when in vent

[Doctor CAD]

I noticed yesterday that there was very cold air coming out of my vents when my selector switch was in Head/Feet vent position.



I opened the hood and quickly found a vacuum hose was off, but that doesn't have anything to do with this problem.



When I have the selector in OFF, nothing

When I move the selector to head only or feet only, nothing

When I move the selector to AC or defrost (both settings), I hear the compressor clutch solenoid click, the rpm's come up a bit and the air gets cold at the vents. All normal



However, when I move the selector to head and feet setting, the same click and rpm change and cold air!



Now I normally leave the selector in head and feet, so my compressor has been running just about constantly.



I pulled the fuse for the clutch solenoid and nothing would maqke it come on, so it is working fine.



What could be wrong, switch?

 

[Kevin Palmer]

The A/C compressor operates in ALL except 2 locations, no matter you want heat or cold air.



This is done so the lubricant circulates within the A/C system for maintenance as well as prevents leaks due to seal drying out when not used long term, such as winter...

 

[Doctor CAD]

If thats true, doesn't it cause a power-robbing/low MPG condition?



I guess I will NEVER use head and feet vent position!