AC/Heater stuck on defrost?

2008 CHEVROLET EXPRESS
27,000 MILES • 6.0L • V8 • 2WD • AUTOMATIC
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DAVID FOWLES
  • MEMBER
  • 1 POST
Temperature blows correctly, but air stuck on defroster.
Nov 4, 2022 at 5:40 AM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,837 POSTS
  • ASE Certified Mechanic
This happens when the HVAC system loses the vacuum supply to the system. Check under the hood and looks for a small vacuum line that heads into the cab this will be the line that is broken. here is a guide that shows what I am talking about, and I have included the defrost actuator so you can check that out as well.

https://www.2carpros.com/articles/air-vents-stay-in-the-defrost-position


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Nov 4, 2022 at 12:23 PM
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