cold air

[cyrylyn]

When I bought my truck and first turned on the a/c, it stayed on whever I restarted the truck, and forced recirc. mode.  A couple of months ago, this was fixed when the dealer replaced the a/c head unit (in the dash) with a new one.  Now, it remembers the climate mode I selected before I turned off the ignition.  However, the coldness problem didn't go away like I had hoped it would.  If I drive down the freeway, with the temp selector on cold, with fresh air coming onto the windshield, the air is somehow ??? cooled almost to the point of a/c, much, much cooler than the ambient temperature outside.  Even when it's triple digits hot out, this thing makes cold "fresh" air.  I have also noticed that the a/c clutch engages every 20 seconds or so, regardless of the climate setting, and it shuts off after a minute or so.  Is this normal?  Has anyone heard of this before?

[Shaners]

If you have the vent setting even 1 degree past 12 O'Clock to the right (towards the defrost and floor/defrost blend positiions), the AC compressor will come on automatically.  That's because you are directing fresh air towards the windshield, and the air that has been cooled by the AC is drier and will aid in a quicker defrost.

[rrsob]

Does the heat/air system have a computer circut? The other week on the way home I noticed it was getting a bit warm in the cab. Turned the temp control to half way. Still too warm. Then when I turned it all the way to cold I noticed the air light was on, and full heat comming out of the vents. The fan switched worked, but the temp switch stayed on full heat and the possition switch stayed on vent, even if I moved it to defrost, floor vent, whatever. When I got home I shut the truck off waited about 30sec. and restarted the truck. Then everything worked fine. I guess it reset as I hoped it would and I have'nt had a problem since. But it puzzles me a bit. Whats up with this? Is there a computer circut. Should I be concerned? ???

[SilveradoWV]

Mine puts out cold air if I have the temp on the coldest setting, AC button is not lit (off), and the recirculate button is lit. The air feels just like the AC (probably is). I told the dealer and they gave me some long   explaination so I just left it the way it was.

[TomEllis]

Mine puts out cold air if I have the temp on the coldest setting, AC button is not lit (off), and the recirculate button is lit. The air feels just like the AC (probably is). I told the dealer and they gave me some long   explaination so I just left it the way it was.

 

If the Recirc. button is on OR the defrost is selected, then the A/C Compressor is engaged. This is to dehumidify the air in the cab of the vehicle.

This is normal.

Tom

[ClipperSkipper]

With ATC cold air will blow out of the dash vents, instead of the floor (like yesterday Sunny 68°) until you select a warmer temp in order to get the blend door to move to floor.

 

Have a great one!

[Tolliverme]

I had a 99 Silverado and then got an 01.  I had similar event.  With AC off, Fan on and recirculate selected the compressor continued to run and I got cold air all the time.  After a couple of trips to service and emails to Chevrolet I was told that they made a software change that made this happen and it is working as it is supposed to.   I don't understand why anyone thinks this is a good change, I sure don't.  Must have been an engineer.

[cyrylyn]

If you have the vent setting even 1 degree past 12 O'Clock to the right (towards the defrost and floor/defrost blend positiions), the AC compressor will come on automatically.  That's because you are directing fresh air towards the windshield, and the air that has been cooled by the AC is drier and will aid in a quicker defrost.

hmm.  thanks for the info - that really sucks.. I'd like to have fresh, non-airconditioned air that isn't blowing on my face or feet.  IMO, the a/c should only be able to come on if you've pushed the button.. imagine if the transfer case did that?