Air conditioner recirc

My wife never uses the auto setting in her car and gets frustrated when I turn it on from the passenger seat, so I just quit trying. Auto and dual zone are features that I honestly never expected to appreciate so much.

 

I love all the educated answers. Especially the saving gas. What, maybe .006 or .007 miles to the gallon?

 

What is the theory behind this?

 

Everybody's posts about recirculating air being more efficient, colder, etc are all correct.

However on hot days, it's a common occurrence that the air inside the vehicle is actually hotter than the air outside.

Opening the windows slightly and running fresh air mode for just a bit will get your AC to work faster to cool the air in the vehicle as you push the really warm air out.

Once you notice it getting cooler (will be significantly faster), then you can go ahead and roll up the windows and switch to recirculation mode.

 

Nope…..that’s BS

 

not a theory- it was the results of testing…

No it’s not “BS” nor is it an opinion.

Sorry I didn’t elaborate this, but you are partially right. Once you’ve cooled off the interior by cracking open the windows and running fresh air, the overall lower cooling requirements of recirculating cool inside air vs cooling heated outside air [once your interior cools off] results in using lower AC blower settings and using the compressor less.

Also did you know that in hot climates, white and other light colored vehicles get better mileage than dark colored ones? It’s really just due to those drivers of light colored vehicles using their AC’s much less than those with darker vehicles.
https://eta.lbl.gov/news/11089/cool-colors-for-cars-could-improve-fuel-economy-reduce-emissions

 

that's bs. recirculate doesn't engage the a/c compressor as often, using less gas.

 

In my 2nd gen, there was a wire you could cut to prevent the recirculate from turning on with the air conditioner. I'm not sure about the 3rd gen though. It seems that more things are controlled though the ECU on this truck. It annoys the hell out of me, too.

 

I drive fleet vehicles with auto climate control and every car partner I've had will crank the temp setting down to 60 degrees and manually set the fan.

Just set it to the temp you want like at your house!

 

The blower also makes the alternator run more often when you crank up the air setting- more use of gas.

 

i guess, but not a significant load like the a/c compressor. anyway, without recirculate my a/c tends to drip on the floor mat in humid weather.

 

I would disagree entirely.

I have poor thermal regulation in my feet. I don't know if it's poor circulation, or what, but my feet are always cold in the winter, no matter how well insulated my boots are, and hot in the summer, even with sandals.

I live and work in Canada. It's not uncommon for me to spend all or part of my day working outside in -20° to -30° Celsius. When I go home at the end of the day, my feet are frozen stiff, even after the rest of my body has warmed up.

I don't care what the cabin air temperature is. I want that hot air blowing on my feet at all times. I don't want the fan cutting out once the computer "thinks" it's the right temperature. If my body gets too hot, I'll crack a window to cool the cabin, but I want that hot air blowing on my feet at all times.

The inverse is true in the summer. I want that cold air blowing on my feet at all times. Especially if I'm in my work boots, after spending all day on a rooftop in the sun. I'll crack the windows to warm up if my body starts getting too cold, but I want that cold air blowing on my feet at all times.

I'll gradually turn down the fan, and adjust the temperature dial, once my feet have reached a comfortable temperature, but the "auto" setting is by no means smart enough to know when to do that.

I can imagine the "auto" setting being useful in the spring and fall, or perhaps on a day trip once the feet are comfortable, but not during a 20-30 minute commute in extreme temperatures.

 

I would have to say you’re in the vast minority where your focus is on feet at all times. I at times have uncomfortable feet temps but I don’t think any automaker in their right mind would make an auto system work to where it prioritizes foot air over all else.

In the winter it blows heat straight at the floor anyways so that shouldn’t be a problem, but of course it doesn’t do that in the summer with cool air because if cool air is just blown to the floor, it will just sit there and nothing in the cab will cool off (except the feet). Thankfully you can still run the system in auto anyways and just change the mode to foot/panel so you get cooling on the feet and chest level. Auto would still keep the fan speed high until it senses the cab is cooled off and if that isn’t enough, just roll the temp knob down to low and it will run that way until told otherwise.

 

My feet are definitely a special case!

A lot of it is subjective, too. I've been driving for 29 years, so you just get used to doing things the way you always have. Some new features you love, some you hate, and some you're indifferent to. You pick and choose which ones you use, and which ones you don't.

I've only had this truck a month, but I've found it rather distracting to have the fan coming on and off. I'd rather set it to a constant speed & temperature, then I can ignore it.

Will I get used to it? Maybe. I thought I'd hate the blindspot monitoring feature, but I'm actually enjoying it. But at this point I'm anticipating that it'll be more of an annoyance than a feature. We'll see how I like it once the weather gets cold.

 

It depends.
I live in Florida and first thing I do is switch off air recirculation for about 5 minutes. This allows AC to pull air from outside which is generally cooler than inside the truck. If you think about it, recirculation keeps air in the truck that was parked outside and it has interior temperature of 120F, so if you're getting into a hot truck, you're essentially trying to cool off 120F air as opposed 90F air that you could be pulling from outside.

I hope this makes sense.