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A/C On When It Is Off



Does anyone know why my air conditioner blows air when everything is off, it does it when i am driving not sitting, kinda weird.
It is suppose do do that. It keeps alittle air flow coming in to the cabin. If it really bothers you, press the button that recirculates the air. (The picture of the truck with arrows cirrculing around in the cabbin) As opposed to the fresh air mode that has the arrow coming from the outside into the cabin.
The temperature control works to change this low flow air too. If you like a little fresh air and it's not cool or warm enough for the fan, you can adjust the temp of the low flow air. Chevy (GM) used to call it "Astro Ventilation" in the early '70's. No...I'm not that old. I just know these things because my folks had a Kingswood station wagon and we couldn't afford A/C back then.

Truckman :B:
ahhhh ok thanks guys, it doesnt bother me just didnt know if mine was the only one.
When you have the a/c button de-activated, recirc on, and fan on, it will still cycle the compressor as if the a/c button was pushed ...

(you don't need to be in defrost for this to happen... it will happen on face, bi-level, and floor)

When in defrost mode, the compressor short cycles... (different)

The only way you can run recirc with no compressor cycling, is turn the fan OFF and hit the recirc button again, then the vents will all close off...

One more thing for y'all. The HVAC system is designed to allow fresh air into the cab, even if the system is off. In this way, it helps to thwart any sort of CO poisoning threats. Most mfgs do this to some degree. I am not sure if it is federally mandated, but it is done!

ciao for now