AC blows warm air, no pressure on high side gauges

Tiny
CMANGUM
  • MEMBER
  • 2011 CHEVROLET SILVERADO
  • 5.3L
  • V8
  • 4WD
  • AUTOMATIC
  • 114,000 MILES
Intermittently cold air will blow for a few minutes. I check Freon and low side reads avg around 50 and high side does not read. I have tried to add Freon and it seems to be full. The compressor does cycle off and on. I evacuated the system and pulled a vacuum on the system and it held 28 for over 12 hours.
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Sunday, May 12th, 2019 AT 4:54 AM

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Tiny
KEN
  • ADMIN
Hello,

If the compressor runs with refrigerant inside and does not build pressure the compressor has gone bad here is a guide to help walk you through the steps of replacing the it and recharging the system with diagrams below to show you on your truck.

https://www.2carpros.com/articles/replace-air-conditioner-compressor

and

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Check out the diagrams (Below). Please let us know what happens.
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Tuesday, May 14th, 2019 AT 11:06 AM
Tiny
KASEKENNY1
  • EXPERT
Hi Cmangum,

More than likely your high gauge is reading a very small amount of pressure but due to it being a higher pressure gauge it looks like it is not reading. If you have pressure on the low side, you will have some amount of pressure on the high side. More than likely it is pretty close to being even pressure on low and high side which basically means you compressor is not building pressure. The fact that you pulled it down and it held a vacuum shows there is no leak but the compressor itself is not building pressure. Any time the compressor is cycling but no pressure is building, it typically means the compressor is not doing anything but spinning. There is a slim chance that you have a complete restriction but that normally always presents itself as a very high pressure on the high side.

I included the procedure to replace the compressor because based on this info, that is the direction it appears to be going.

Let me know if I am missing something or didn't understand what your issue is. Thanks

https://www.2carpros.com/articles/replace-air-conditioner-compressor
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Tuesday, May 14th, 2019 AT 11:32 AM

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