Hey all,
I have had an issue for about 2-3 years with my A/C.
I think I have finally gotten it fixed but wondering if it is acting correctly (or at least like other H2s)

First off it is an 03 (in case it makes a difference)

My A/C will blow cool to cold air when the fan is on full blast and the setting on 60.
So I use the temp on 60 and the fan on high to get the rig cool from these HOT days. The thing is I have a temp probe in the center A/C vent and with the fan on high and the temp at 60, it will get down to rougly 60ish. (60-62-64).
BUT, if I drop the fan speed down to only 3 bars, the A/C drops to like 42 degrees according to the probe.
Now I have also noticed that if I sit at a light the temp will go up at times. Given, it doesnt seem to go much higher then the originally stated 60-62-64, but it will at times go up.
As long as I am driving.... it stays at near freezing temps.

Also understand that it has been in the mid 90s here with HIGH humidity and STRONG sun/UV ratings

I am not complaining, just making sure that 1) this is normal and 2) others have this going on.

Just trying to make sure i dont end up with another issue because something wasnt fixed right.

Thanks

 

AC will always blow colder on lower fan speed settings. The air has more time to to get colder when it passes by the evaporater.

 

Mine is an 03 and does the exact same thing. Have not figured it out yet. Where are you located with the temp and humidity like that? Im in Louisiana

 

Gulf Coast, MS

 

This, running an AC on max is much less efficient than a couple bars under max. That is why I have NEVER put mine on auto as its a waste of time and air. Also an AC compressor will cycle on and off. I think you're looking too much into the temp probing.

 

Mine sometimes takes up to 2 minutes to come on from when I start the truck. Does not matter if in auto or manual. Not sure what is causing this either.

 

It's all normal. A/C compressor needs to run to cool the evaporator (where the air blows through and cools down). This takes time, and at idle it may not be able to to keep things as cool. The A/C stuff is an on-off process, the temp in the evaporator when everything is working correct should stay in a certain range. The fiddling you do at the heat/ac controls only changes the speed of air across the evaporator and how much the cold air is mixed with warmer air before it comes out the vents.

 

I found the issue that was causing mine to get warmer at stops ect.. The fresh air door behind the glove box was stuck open, the recirculation motor was not working. I pushed it closed and sealed with gorilla tape. The h2 will literally freeze you out no matter what fan speed its on now.

 

Happens not only to Hummer but almost every car . ,Max Ac will not be as efficiency ..
Im from sunshine state which become the rainy state lately . Summer avg temp here is 98 with 100% hum ... I use to remote start the truck with the Ac on , fan low-mid 3-5 min before get in , this made the temp nice but not cold a all .
In fact I never felt cold temp inside the truck while is 98 outside