Ac
 

Ok guys, this is the problem I'm having with the AC, if you turn on AC with the thermostat on the coldest setting it will blow hot air, if you move the thermostat up two to three clicks it will blow cool air after you drive ten miles you can move it down to the coldest setting it will blow cold air and work ok, I say this for its ten miles to town and I check it every day, if you put the thermostat to the coldest setting before you go ten miles it will blow hot air, This issue isn't nothing new to the car, its been going on now for two years, I've taken it to the dealership twice and both times it wouldn't act up for them,once they said it had too much freon any comments on this issue.

2006 HHR LT 121k miles

Just for starters; you do have the thermostat turned all the way counter-clockwise for coldest setting? I ask this because my wife and my neighbor both think that coldest is at the point were red and blue meet, evidently it's a common idea.

Set on fresh air?

My other guesses would be a blend door malfunction or a diverter door malfunction.

yes donbrew,its turned counter all the way, but it does seem like you said a blend door malfunction, I'm not familiar with that. it does seem as tho something is not opening or shutting correctly

Check your PM topgunn.