A/C not very cold....It's 100 degree outside! [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: A/C not very cold....It's 100 degree outside!

07-16-2006, 04:50 PM
I have lately noticed that my AC temperature doesnt blow out near as cold, Sometimes i have to floor the gas to get it colder, I know the digital gauge says 60 degrees but its closer to 70 or 72 when coming out, maybe 15 mins later its down to 60 degrees blowing....

What does this sound like? Thanks


Envoy Fan
07-16-2006, 04:54 PM
The fan clutch could be going bad.

07-16-2006, 05:37 PM
do you have the recirculation button engaged? If not, it's really not going to get that cold, because it's having to convert that 100+ degree outside air to cool air on the inside for you. Whereas if youhave it recirculating, it has cooler air to work with, therefor it makes it easier for the AC to get it to the desired temp. ;)

07-16-2006, 05:52 PM
mine feels like that too. It just started the other day when i got in...i was like "it usually gets colder than this" I had to double check to make sure it was on the coldest setting.

07-17-2006, 10:43 AM
It's just the way the system works....physical limitations and all. At that high temperature outside, the system is unable to remove as much heat from the coolant, therefore it's unable to remove as much heat from the air entering the passenger compartment. :crazy:

07-17-2006, 10:45 AM
Even at high speeds its not cold? Mine isn't too cold when idling.

07-17-2006, 11:50 AM
Part of what you're noticing may be that the digital climate control switching from recirc to vent after a period of time. Actually it will start in vent, until the cabin temp cools below ambient, go into recirc until you get close to the set temperature and then switch back to vent mode to maintain the temperature for prolonged periods of time. (You can override that my manually selecting recirc mode....might help). In recirc mode, the already cooled cabin air is drawn into the system and sent back across the evaporator making it even colder as opposed to taking outside 100 degree air and trying to cool it. (An a/c or refrigeration unit generally can cool air around 35-40 degrees at optimal settings

If you idling or stopped in traffic for prolonged periods of time, the air will not be as cold.....no system will be. At idle you're not moving enough air past the condensor to maintain the absolute coldest settings, nor is the compressor spinning fast enough to compress the refrigerant optimally. In order to pull heat from the air, you need to remove the same amount of heat (at minimum) at the condensor.....and that's just not going to happen at 600 rpm idle on nearly any vehicle on a hot muggy day. (Humidity also plays a key role in how much heat is removed by the system, the higher the humidity the less efficient an a/c unit becomes). Also take into consideration it could take several minutes of driving before the system reaches full capacity, depending upon current conditions if the vehicle has heat soaked in the sun after being run on a really hot day.

07-20-2006, 10:47 AM
There is a TSB to replace the fan clutch, cured the AC problem in our '05. Ours wouldn't blow cold at idle, and took a minute or two at speed to cool off. Problem is the fan doesn't pull enough air over the condensor I guess, surprised the TB doesn't overheat.

07-20-2006, 10:52 AM
I agree with all the comments about recirc. Around here in the summer we get Houston like humidity along with the heat. I always start out with the AC on regular and then switch to recirc after the interior starts to cool. I've found this cools the inside off much faster. Also, I crack the sunroof to the "vent" position and that sucks out the heat.

Both my vehicles have the auto CC but I usually leave the temp on 60 and manually adjust the recirc and fan speeds.

07-20-2006, 01:19 PM
I had the same problem on my 05 EXT. Parts are on order.