Re-circulated Air Button

[Guardian]

My 08 LT3 has a button that re-circulates the inside air when turned on. My dealer says that it is best to have this turned on anytime I am using the A/C. It does keep outside air from coming into the cabin and lowers your chance of outside smells stinking up your vehicle!

My question: Is it really necessary to keep this on when I have the A/C on? Also, if it's best to operate with it on, why doesn't it stay on after I turn the engine off and then re-start the truck? I have to manually push this button on every time even though the A/C will come right back on automatically.

Thanks!

 

[AZSCTACO]

They recommend to use it during the summer time because it is easier to cool....already cooled air instead of the truck trying to cool down 100 degree outside air. With that being said....I think it is retarded that it automatically turns the recirc button off every time you turn the truck off. Wish there was a fix for this.

 

[Gambler]

I think it is off by default because on a hot summer day, the temp inside the car is much higher than outside the car. So when you start the car it will by default use the cooler outside air, then once the car starts to cool off you can switch it to recirculate so it uses the now cooler inside air.

 

[Rafael]

I think it does a very bad job of recirculating the air. I still can smell exhaust with the button depressed.

 

[Mad Dawg]

I just set the whole system on "Auto" and forget about it, only to adjust temp as needed for the outside conditions.

 

[Guardian]

I have mine on "auto" all the time also, but it doesn't effect the re-circulate button. I think it should be smart enough to determine when to stay on and when it needs to go off. Just kind of strange that I have to keep turning it on all the time.

 

[Tahoe07]

It defaults to off because you should not run it all the time.

BTW it still lets in a percentage of fresh air so you don't build up CO2 or CO as you drive.

 

[allando]

If I'm not mistaken, the recirculate button is also the "max a/c" button as well.

 

[Getwired]

...BTW it still lets in a percentage of fresh air so you don't build up CO2 or CO as you drive.

Keeping it off helps keep the humidity equalized as well; like on those hot muggy nights when your windows won't quit fogging up inside.

And ALSO, I would recommend to turn OFF recirculate occasionally if you're using the A/C a lot, like maybe 10 minutes before you get to your destination on a long drive. Why? If you're running it all the time on recirc, you risk mold / mildew growing in the evaporator coil, which will give off a really nasty musty stank and ruin the pleasurable drive. I hear that the GMT900's are better with that, because there's supposedly a fan / drain in there that dries out the coil after it's been run, but I dunno for sure. Anyone know this for sure?