Hello. I have a 2007 HHR. When the temperature dial is all the way to the left I get warm to hot air. I need to move it up a couple notches to get normal air temp. Can this be repaired or is the unit wearing out?

 

Sounds like a problem with the "blend door" either the actuator or the door itself. I think Advance can order the parts for you, but it's a minor PITA job.