Heater not working

2004 CHEVROLET AVALANCHE
120,000 MILES • V8 • 4WD • AUTOMATIC
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DENISE WHITE
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  • 2 POSTS
I had issues in the past where I could not get the air to come down to the vents or it would be hot air. Still having issues but now I only have cold air blowing no heat at all.
Dec 7, 2017 at 9:28 AM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Start the engine and turn the heater on high. Allow the engine to reach operating temperature. At this point, feel both heater core hoses. Both should be hot. If they are, you have a bad blend air door actuator.

https://www.2carpros.com/articles/replace-blend-door-motor

If only one is hot and the other cold, suspect a plugged heater core. Here is a list of the most common problems:


https://www.youtube.com/watch?v=SNRb6pSwYuU

Let me know what you find.
Dec 7, 2017 at 6:48 PM
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DENISE WHITE
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I checked the hoses one is hot the other one was barely warm.
Dec 10, 2017 at 3:21 PM
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STRAILER
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 54,178 POSTS
Yep it sounds like you have a plugged heater core. Can you remove the heater hoses and use a garden hose to blow through it please?

Here is a guide that can help you as well.

https://www.2carpros.com/articles/car-heater-not-working

Please let us know what happens.

Cheers, Ken
Dec 16, 2017 at 1:14 PM