2015 Chev Silverado 1500

[S_Penny]

We recently had to have our air compressor replaced on our 2015 chevy silverado with 75,000 miles. Just stopped blowing cold air.  After we picked up the car from the mechanic we noticed that there was a whining noise when using the air conditioner that would get louder as you picked up speed.  If you turned off the air you no longer heard the whining. We took it back and of course they said there was nothing wrong and said we should have the Transmission fluid checked.  We took it to a transmission shop and they said it was a little dirty, but did not to be changed. The Transmission shop owner thought the noise could be the Serpentine Belt Tensioner Pulley Assembly. So we had it replaced. The whining is still happening. I asked the mechanic that replaced the air compressor if it could be bad.  They said there was nothing wrong with it.  Should I take it to a GM dealer? I did tell him i might do that and his response was "if they tell you the compressor is bad, don't let them fix it bring it back to them". 

[Snowcamo]

Iirc I cut the bet off the ac compressor when mine locked up recently.

 

It's on its own belt if 5.3 v8. Likely the belt needs to be replaced or needs more tension.

[rav3]

1 hour ago, Snowcamo said:

Iirc I cut the bet off the ac compressor when mine locked up recently.

 

It's on its own belt if 5.3 v8. Likely the belt needs to be replaced or needs more tension.

Fyi, there isn't any adjustment on the A/C belt. It's made to stretch into place.

[Scupper]

I had the same wining noise.  I recently had to had the same issue on my 2015,  no cold air.  I tried freon with the leak inhibitor.  That would last about three days.    The wining would be on if I had the AC on.  

My buddy checked out the AC unit with a sniffer (detects freon leaks).  the condenser coil was shot.  We found this is very common in GM's.  The condenser is in front of the radiator and subject to welds failing due to road salt. 

We replaced the condenser coil from Rock Auto, less than $150.  I got the upgraded one with some special coating on the aluminum.  Borrowed a hvac evac machine, + the freon and we were done.  Took about 4 hours.  No more wining noise and cold air. 

[S_Penny]

When you say the belt needs to be replaced are you talking about the Serpetine Belt Tensioner Pulley. If so, we did replace that and the whining is still there.

 

I just found out recently that the condenser should have been replaced at the same time. I am upset now to learn that the mechanic did not do that. 

 

Thanks everyone for your input!