H3 AC Problem, fan blowing hot air...

[bull5]

Hi all,
I have an AC problem with my Hummer: Fan is blowing hot air.

I have changed so far:

Compressor
Condensator
Dryer
Freon has been refilled

Compressor engage, looks fine.

HVCA has been calibrated, but no way....

Any suggestion?

 

[VIPNiSS]

Hi all,
I have an AC problem with my Hummer: Fan is blowing hot air.

I have changed so far:

Compressor
Condensator
Dryer
Freon has been refilled

Compressor engage, looks fine.

HVCA has been calibrated, but no way....

Any suggestion?

it's possible your temperature control knob is bad and not adjusting to cold air.

look at this thread and try this mod..

http://www.hummer4x4offroad.com/forum/showthread.php?3962-Climate-Control-fix

 

[bull5]

What about the expansion valve?

The old compressor was faulty. Can be that the expansion valve is obstructed?

 

[mjferencak]

You said it's been calibrated... meaning you did a leak test and pulled vacuum before filling with freon?

Oh I forgot about the issue I had with my AC blowing hot. Have you changed out the HVAC wiring harness? There is a recall on it.

Dang I forgot I did the resistor thing also. I've worked on my truck so many times I've forgot most of what I've done. Just ask my wife. Every time I buy something for it she replies "Again!!!?":giggle:

 

[08H3]

As much as I hate to take my cars to a mechanic, I think you are at that point. You've already thrown some pretty serious money at it changing out the compressor and condenser. I'd personally cut my losses at this point.

 

[bull5]

Yes leaking and vacuum done so far.

 

[Ryan212]

are the lines under the hood getting cold or hot? High and lowside pressure readings? Did you use a real machine to fill the system with R134a or did you use the gauge on a can? that only connects to the low port

 

[Hunner]

Might be a 13 cent fix!

 

[humvee]

Does it blow cooler or less warm air when you're at higher speed? If so, check for airflow restriction.
Have you recently installed anything that restricts airflow to the engine bay? I had this when I installed a large trans cooler along with the v8 swap.

All it needed was an e-fan up front to help push air in, and all was solved.

 

[RoadWarrior]

My guess is get the HVAC recall performed. Behind the glove box is a pin-connector that shorts...everybody's does eventually. GM Shop will know exactly what to look for and easy fix.

 

[humvee]

That is probably it. My AC only cools when the temp nob is set to minimum. One click up and it blows hot air.
Dealership will fix that for free before you try anything else.


Sent from my iPhone using Tapatalk

 

[bull5]

It doesn't cool down if the nob is set to the minimum so should not be the hvac the problem. Hvac recall has been done (in this case the blower was off, I'm my case the blower runs). I have to check if the pipe lines are freezing. But I have canghed everything except the expansion valve. The tubes connected to the expansion valve are not hot but not really iced...

 

[Hunner]

The recall will not fix the issue of the temperature setting knob allowing hot air to come out when set at anything other than lower temperatures. That only prevents the blower motor from causing the connection from melting.

Fix both.
http://www.hummer4x4offroad.com/for...etter-Attached&p=196702&viewfull=1#post196702

 

[bull5]

The recall will not fix the issue of the temperature setting knob allowing hot air to come out when set at lower temperatures. That only prevents the blower motor from causing the connection from melting.

Fix both.
http://www.hummer4x4offroad.com/for...etter-Attached&p=196702&viewfull=1#post196702

Ok I have installed the 70 ohm resistor. The problem persist.... The line under the hood have the same temperature. That is strange. Compressor looks OK.

 

[bull5]

Sorted the Problem was the expansion valve faulty...

 

[humvee]

How was the fault singled out?


Sent from my iPhone using Tapatalk

 

[bull5]

Compressor cycle of 4 seconds pressure ok not cooling down

 

[Kiwi.NZ]

That is probably it. My AC only cools when the temp nob is set to minimum. One click up and it blows hot air.
Dealership will fix that for free before you try anything else.


Sent from my iPhone using Tapatalk

Hi there,
I have the exact same problem with my hummer h3, can you please tell me what you did to fix this issue.

 

[Kiwi.NZ]

Hi there,
I have the exact same problem with my hummer h3, can you please tell me what you did to fix this issue.

I live in France so I don't think hummer dealership will fix this issue here.

 

[H3Hummer]

Bonjour voisin

Mine did blow hot too after a short with battery, checked all fuses of the AC and it was final just the dumb relais. Changed the relais and the AC worked fine again.

 

[H3Hummer]

And welcome to H40, any pictures of your rig?mods done ?

 

[Kiwi.NZ]

Bonjour voisin

Mine did blow hot too after a short with battery, checked all fuses of the AC and it was final just the dumb relais. Changed the relais and the AC worked fine again.

Hi, thanks for that I will check that, but just to confirm, was your heater with or without the AC running cool down low, but when I turn the dial one notch the temperature would just run hot.

 

[H3Hummer]

Mine was only the AC not getting cold! The heater was working fine. Check your fuses : 53 ,59 , 82, 87 + diode 90

 

[Kiwi.NZ]

Thanks for replying, I will check those fuses

 

[Kiwi.NZ]

That is probably it. My AC only cools when the temp nob is set to minimum. One click up and it blows hot air.
Dealership will fix that for free before you try anything else.


Sent from my iPhone using Tapatalk

Hi, I have got exactly the same issue, My AC only cools when the temp nob is set to minimum. One click up and it blows hot air. Can you tell me exactly how you fixed it please.