A/C with Air recirculation on????

Raiderse · August 12, 2015

I am wondering if you all still smell any outside odors like if your going through an area when where there is a smoke smell from burning or a sulfur smell maybe from stagnant water etc. through the vents with the A/C on even when you put the air in recirculation. I still get some of the outside odor didn't on my Fords. wondering if maybe some ducting is not sealed correctly or if this is normal for the Chevy/GMC?

I guess the simplest way to ask what I am asking would be do you still get some outside odor when you have your a/c on and press the cabin air recirculation button?

Edited August 12, 2015 by Raiderse

Britt Lifsey · August 12, 2015

Don't know as fact but I've always heard the recirculating mode still brings in small percentage of fresh air...

I usually don't notice any odors but our dog keeps her nose to the vents smelling for something :-)

Edited August 12, 2015 by blifsey

jimbo285 · August 13, 2015

Never noticed any odors coming inside on recirculate, but the other day I turned recirculate off and got a huge whiff of forest fire. Alaska is on fire! Turned back to recirculate and smell went away.

2Speed · August 13, 2015

Is there a setting to put it on recirculate, when you hit AUTO and crank it down to LO? I always have to hit recirc manually.

14silverado4.3 · August 13, 2015

I noticed that when I run this on the highway with windows up there is more resonance in the cab

Raiderse · August 13, 2015

Is there a setting to put it on recirculate, when you hit AUTO and crank it down to LO? I always have to hit recirc manually.

It's a button on the dash

newdude · August 13, 2015

The recirculation on K2 trucks was changed. It used to be that the recirculation door closed 100% but was changed to 90% closed so there is some fresh air that is allowed inside during recirculation. Trucks built before 01/07/2014 have the original calibration which was 100% closed.

It was changed due to excessive dust intruding into the cabin during recirculation. See below:

Some
Condition/Concern
Some customers may comment that they have excessive dust intruding into the cabin of their pickup. This concern will be more noticeable when the HVAC is in recirculation mode. When in recirculation mode, the outside air is completely closed off and the HVAC system is recirculating 100% of the cabin air. This will cause very low cabin pressure and may allow dust to enter the cabin at various locations.

GM Engineering has released updated HVAC calibrations which will close the recirculation door 90% when in recirculation mode. This will allow the HVAC system to draw in approximately 10% outside air, thus slightly pressurizing the cabin, making it more difficult for dust to enter the cabin. This is similar to how the previous generation truck's recirculation mode operated.

Note: This new calibration may have a marginal decrease in HVAC cooling and slightly more outside ambient noise being heard in the cabin, while in recirculation mode.

Raiderse · August 14, 2015

The recirculation on K2 trucks was changed. It used to be that the recirculation door closed 100% but was changed to 90% closed so there is some fresh air that is allowed inside during recirculation. Trucks built before 01/07/2014 have the original calibration which was 100% closed.

It was changed due to excessive dust intruding into the cabin during recirculation. See below:

Excellent Information that explains it! This forum is fantastic. Answers to questions that are no exactly straight forward ! Thanks for this info. This hits the nail right on the head.

2Speed · August 14, 2015

It's a button on the dash

Yes I got that...

My question was, is there a way to set the "AUTO" program in the HVAC to turn on recirc by default. I don't want to hit the button every time I turn on the A/C.

newdude · August 14, 2015

Automatic Operation

The system automatically controls the fan speed, air delivery, air conditioning, and recirculation in order to heat or cool the vehicle to the desired temperature.

When the indicator light is on, the system is in full automatic operation. If the air delivery mode or fan setting is manually adjusted, the auto indicator turns off and displays will show the selected settings.

To place the system in automatic mode:

Press AUTO.

Set the driver and passenger temperature.
To find your comfort setting, start with 22 °C (72 °F) and allow the system time to stabilize. Then adjust the temperature as needed for best comfort.

To improve fuel efficiency and to cool the vehicle faster, recirculation may be automatically selected in warm weather.

The recirculation light will not come on when automatically controlled. Press @ to manually select recirculation; press it again to select outside air.

Do not cover the solar sensor on the top of the instrument panel near the windshield. This sensor regulates air temperature based on sun load. See “Sensors” later in this section.

Latte · October 21, 2015

Hello,

I have a 2015 Silverado 4x4 LT and when it is in recirculating mode I can smell fires,diesel,rich running g cars,dumps,sewage plants and any other smell.I believe I read that the a/c door only closes 90% now.I really don't think I would smell e erg thing so easily.I have had a '13 and '14 Silverado LT 4x4 and never any issues.

I find it hard to believe that my '14 is any different then my'15

Any other people with similar issues?

chuckl1218 · October 21, 2015

Hello,

I have a 2015 Silverado 4x4 LT and when it is in recirculating mode I can smell fires,diesel,rich running g cars,dumps,sewage plants and any other smell.I believe I read that the a/c door only closes 90% now.I really don't think I would smell e erg thing so easily.I have had a '13 and '14 Silverado LT 4x4 and never any issues.

I find it hard to believe that my '14 is any different then my'15

Any other people with similar issues?

As stated above by 15HDriver in post #7, trucks built before 1/07/14 have the original 100% closed calibration. So, yes, your 2013 had the100% calibration and your 2014 may have 100% calibration. Your 2015 most likely has the 90%. This can make a big difference in the way air is drawn in.

Latte · October 21, 2015

Hello,

Yeah,seen that post a little while ago.Kind of frustrating explaining to people that have ridden in my '14 that have been in the new '15 and complain about smelling outdoor odors.

Thank you for replying.

Dan