Hello,
I have been reading quite a few posts about AC issues with suburbans however, I have not been able to diagnose the issue yet. In the past month, we have had the left side door actuator replaced due to hot air blowing from the AC (all vents). That issue was either part of or masking an issue where the AC blows hot when at a stop. I took it back to the same dealership but they could not find any issue with it or codes. They evacuated and recharged the system.

In the morning, the AC blows ok. I live in Texas (Houston) so morning temps right now are in the low to mid 80s. I can tell the AC is not as cold as other vehicles, but I attribute it to the size of the suburban and that it takes some time to cool off (seems reasonable). Once I have been at highway speeds for a few minutes, it blows cold but when slowing or stopping, you can feel a change in the temp.

In the afternoons, when the temp is about 95 or higher, the bigger issue arises. The AC will blow warm, then semi cool, then back to warm with each stop and go. The AC will not blow cold until I have been at highway speeds for about 5-10 minutes and even then, you can feel a change in the cold air each time you slow down.

Has anyone had a similar problem?

Thank you

 

Sounds like a lack of airflow over the condenser coil. It only blows cool/cold when you're moving at high speed. The fan, by itself, can't move enough air.

Check the fins in your coils. Are they filled with leaves/dead bugs/etc? Hit them with a garden hose to flush them out. Don't use high-pressure. Might do the trick. Pull off the grille if you really want to get into it.

Otherwise, you might have a problem with the compressor.

 

Hi Whatawest,

I’m sorry to hear that you have been experiencing difficulties with you’re A/C. I understand that you have taken your vehicle to your dealer for this concern and that your concern has not been resolved. If interested, we will like to contact another dealer on your behalf for a second opinion. Feel free to send us a private message with your full contact information, VIN, current mileage, and dealership name if we can help with your concern. We look forward to hearing from you!

Kristen A.
Chevrolet Customer Care

 

Whatawest: Welcome to the forum.

Does your coolant temperature stay around 200 degrees when you are stopped? If not, then maybe your fan is not turning on properly.

I know you just had it recharged but perhaps it is undercharged.

 

The coolant temp stays put right at 210.

 

A/C compressor belt slippage?

 

I am hoping it is something simple like that, but I would hope the 1st dealer would have checked that originally. Maybe I overestimate their investigative skills outside of the code reader.

 

Took it into a different dealer. They tested it and said the program that was running the compressor was cycling it to much and basically keeping it in a type of defrost mode. They also noted the suburban was idling a bit low. They reprogrammed the hvac and idle systems. It does seem to idle at slightly higher RPMs now and I have not had the ac switch between warm and cool yet. Hopefully it was corrected. AC wasn't blowing ice cold but I contribute it to the fact is was close to 100 today and the suburban is black on black.

Only problem I now notice is that the passenger side does not blow as hard as the driver side (noticed before this trip to dealer.