AC blows hot

[danrondeau]

Need help getting AC COLDER.

2007 Tahoe 5.3l, 140k. AC blows 75-80deg F and 60-65deg F on recirc. Brand new Denso OEM compressor, low PSI 45-50/ high psi 225-250, installed cabin air filter kit. The recirc door moves perfect and the Hot/Cold controls seem to be working correctly and evenly on both side. All AC parts/accessories are very clean with no dirt or buildup on them

any ideas?
Thank you!

 

[Just Fishing]

I never bothered to check air temps, but my wifes Buick was not as cold as it should be.
Everything looked great, so on a whim i decided to toss a 1/2 lb into the system.

There was an improvement noticed, so i added the other 1/2lb until i was happy with it...
If you add to much the compressor will begin to cycle on and off with a nice click, the same is true if there is not enough.

Other places to check would be the condenser in front of the radiator
It could be plugged with crap.
if it can't remove the heat, then it won't cool very well either.

And on my 09 hoe, the entire system with rear ac only holds 2.5lbs of refrigerant.
My system has a new compressor and drier, and it's nice and cold with it being 100f outside.

If you didn't do the drier with the compressor, then you need to go back and replace it.

 

[Doubeleive]

Need help getting AC COLDER.

2007 Tahoe 5.3l, 140k. AC blows 75-80deg F and 60-65deg F on recirc. Brand new Denso OEM compressor, low PSI 45-50/ high psi 225-250, installed cabin air filter kit. The recirc door moves perfect and the Hot/Cold controls seem to be working correctly and evenly on both side. All AC parts/accessories are very clean with no dirt or buildup on them

any ideas?
Thank you!

you need a tech2 or similar capable tool to monitor the system and see what the actual temp is showing versus what is commanded. could be a temp sensor, could be the actuator or something else.

 

[Dantheman1540]

Whats the ambient temp? I have had better results with closer to 60psi on the low side but, its typically 90*+ when I hook up gauges.

 

[danrondeau]

Whats the ambient temp? I have had better results with closer to 60psi on the low side but, its typically 90*+ when I hook up gauges.

I live in Phoenix so it’s current like 105-110 outside. That being said, I have a thermometer placed in the grill to get a reading and it’s only 75-80. It’ll get slightly cooler with recirculate. My Tahoe used to get VERY cold! I might try putting a new dryer and condenser on it but I really don’t think that’s it. I might have better results with a blend door actuator or something… I dunno

 

[danrondeau]

you need a tech2 or similar capable tool to monitor the system and see what the actual temp is showing versus what is commanded. could be a temp sensor, could be the actuator or something else.

I threw a thermometer in the air vents to get my readings. I really don’t think my dryer or condenser is bad but I might try new ones just to rule it out. I have a feeling it’s a blend door actuator or something else electrical

 

[danrondeau]

I never bothered to check air temps, but my wifes Buick was not as cold as it should be.
Everything looked great, so on a whim i decided to toss a 1/2 lb into the system.

There was an improvement noticed, so i added the other 1/2lb until i was happy with it...
If you add to much the compressor will begin to cycle on and off with a nice click, the same is true if there is not enough.

Other places to check would be the condenser in front of the radiator
It could be plugged with crap.
if it can't remove the heat, then it won't cool very well either.

And on my 09 hoe, the entire system with rear ac only holds 2.5lbs of refrigerant.
My system has a new compressor and drier, and it's nice and cold with it being 100f outside.

If you didn't do the drier with the compressor, then you need to go back and replace it.

I didn’t do a dryer when I replaced it and now I’m kickin myself. However, we pulled vacuum on it to purge the system so I’m pretty sure it’s good. I live it Phoenix so a cold AC system is important to us

 

[Doubeleive]

I threw a thermometer in the air vents to get my readings. I really don’t think my dryer or condenser is bad but I might try new ones just to rule it out. I have a feeling it’s a blend door actuator or something else electrical

that is not the test I am referring to, the test I mean is to connect a tech2 and see what temperature the system is commanding -versus- what it thinks it is getting-versus-actual temp. so if you set it to 60deg, and it is commanding something else it is a problem, if it is commanding 60deg and shows it is getting 70deg but is really only making 85 it is another problem, etc. there are sensors in the headliner, if one of those sensors is reading incorrectly that could be a problem, if the actuator is goofy that could be a problem.
if all that is good and it just isn't getting cold period then you have another problem.

 

[Just Fishing]

I didn’t do a dryer when I replaced it and now I’m kickin myself. However, we pulled vacuum on it to purge the system so I’m pretty sure it’s good. I live it Phoenix so a cold AC system is important to us

Rule i always followed, if you open the system for more than 10min, the drier needs to be replaced.


If it has been in the system for more than a year, then replace it anyways.

 

[Geotrash]

Need help getting AC COLDER.

2007 Tahoe 5.3l, 140k. AC blows 75-80deg F and 60-65deg F on recirc. Brand new Denso OEM compressor, low PSI 45-50/ high psi 225-250, installed cabin air filter kit. The recirc door moves perfect and the Hot/Cold controls seem to be working correctly and evenly on both side. All AC parts/accessories are very clean with no dirt or buildup on them

any ideas?
Thank you!

When you added refrigerant to the system after the work was performed, did you do it by weight? If not, then there is no way to know if you have enough in the system because the pressures won't tell you much.

 

[CaptainAmerica1]

 

[Snowbound]

Your over charged or condenser restriction. Period exclamation mark end of sentence. Pressures are too high!

 

[Snowbound]

30-35 on low side
140-170 on high side

 

[Snowbound]

Why the new compressor? Internal failure? If so you should have replaced condenser, accumulator, orifice tube, and flushed the lines and evaporator at a minimum. Compressor come with pag oil in it already? Should have. And then needs to be turned by hand to move the oil not just charged and started.

 

[Snowbound]

I had a clutch failure and thought I was gonna throw a compressor kit at it (comp, orifice, accumulator) until I seen metal shavings all over orifice tube while taking it apart. Must have had a compressor failure on previous owner and they just put a compressor on it.

Post #249 and 250

I’m back with an Esky this time

Thanks so much for sharing! Awesome post! Here’s my kiddo, who is turning 13 this year! [emoji15] Congrats! Miss my kids--all grown up :(

www.tahoeyukonforum.com

 

[Just Fishing]

I did mine proactively before i had any issues, other than an odd noise noticed when the ac was running it only had high miles.

I did a full compressor dissemble to confirm no metal and to ensure i accounted for all of the oil, otherwise i was prepared to flush the system.
If i saw metal, i probably would have replaced the condenser with it.

I also pulled the orifice and the little screen under it for the rear ac, all looked great so i did a very careful and detailed oil balance.
No guessing, be 100% sure i accounted for the oil removed, and added back any that the new compressor didn't contain.

the orifice was replaced with the updated OEM style, I never could find the pn for the rear ac screen so i just cleaned it and replaced it's little seal.

And of course, per the factory manual I added the extra oil to the compressor and not the drier/accumulator.