AC Question

[Rob Allen]

Hey Boys & Girls, Just a quick A/C Question. How does MAX AIR work, or when should I use it?

 

[shawn stonbraker 2]

Max air is it takes the air out of the cab instead of from the outside. The air comming out of the vents into the cab will be ALOT cooler, since it is taking the already cool air bake into the system. At least that's how I think it works. I'm probably wrong.

 

[Dave S 2]

MAX A/C should be used if you get in the vehicle and it is really hot. It will recirculate the cabin air (stale) rather than outside air so it will cool a lot quicker. While in the MAX position, you should have a window cracked to pull at least a little fresh air in. Once the cabin air is comfortable, switch the A/C to normal. It will then switch vent to outside (fresh air) into the cabin.



I believe this (fresh air) is thanks to Ralph Nader.



Hope this helps...

 

[Todd Z]

It does run the compressor longer too...



AND it is great if you have a stinky truck or car in front of you on the road..



Todd Z

 

[KentheREALone Z]

So true. Also use Max when in traffic so you're not sucking in other car exaust laden air.

 

[Johnny O]

If you leave it on Max all the time however, the inside of the windows can fog up because it does not dehumidify the car.

 

[DAN PETERSON]

Somebody should make a filter for the ST's vent, my 02 Focus had one. It used a Purolator carbon/hepa filter which cleaned the air so well, even when behind a stinker. The cartridge installed below the passenger side windshield vent. Is the vent intake the same on the ST?

All one has to do is cut a good furnace filter or a home air cleaner filter and stick it in the vent opening, I bet this has been done before on the ST.

 

[Greg Stuhlsatz]

I only use the max.

 

[Chase Straw]

MAX A/C actually does dehumidify the air. air can only hold so much moisture at a given temp if you drop let say 100 degree inside cabin air down to 40 degrees, the moisture that was sustained in 100 degrees now turns to condensate or water droplets and falls (this is the water you see dripping out of the bottom of your car when using a/c) The air that goes out the vent now raises to the cabin temperature but still has 40 degrees worth of water vapor in it. and this class is a/c 101

 

[David Humphrey]

Interesting everone seems to have their own way of using max A/C. I do the exact opposite as Dave does. I am not A/C expert but it seems simple to me.



When I first get in and the vehicle is really hot, I use normal A/C, because the air inside is so hot and it takes a while to cool it off, so the outside air is much cooler than the inside air (say, 90 outside vs 110+ inside on a typical day in Nebraska for example).



Once the cabin is cooled off a bit (maybe 5-10 minutes) then I switch to Max A/C, which usually means I can lower the fan speed or raise the temperature of the air so it's not so darn cold. Then the system does not have to work so hard to cool the air since the cabin air is cooler than the outside air.



It seems natural to me, I've never heard of anyone using them the other way around. Recirculating already hot air seems silly to me and then once the vehicle gets cool using the hot outside air - seems backwards. If the temperature outside is say 90 and the inside temp is say 80 then it would make sence, but then you wouldn't really need much, if any a/c at all anyways.

 

[jbluther]

I agree with you, David.



However, Max A/C, as Todd Z mentioned, I believe has longer compressor cycles. For the sake of compressor life and fuel MPG, it's probably better to run the regular A/C while cruising. The differences are probably negligible. Just offering a different point of view.



Having said that, my 2001 doesn't seem to quite keep up on very hot days on "normal" A/C. I find myself turning it to Max fairly often.

 

[Rob Allen]

Dave, the way you use yours is the exact way my salesman told me to use it when I bought the vehicle.

 

[Dreman]

When I first get in, I put it on normal AC, point all the vents down, and punch the button to vent the rear window. That seems to get the hot air out faster, since I'm pumping colder air in down low from outside, and letting the hot air out at the top. When it cools enough to get rid of the "oven" feeling, I close the rear window, flip the vents up, and turn to max AC to bring it down to normal room temperature. When it starts feeling cold, I turn it to normal AC again so I can adjust the temp.



Just another way of dealing with hot Texas car interiors! If it's really hot out, and I have a minute, I'll turn the truck on and run all five windows down for a minute before I even get in!

 

[Gavin Allan]

I hardly ever use Max A/C. I want fresh air in my truck, not recirulating stale dirty air. If it is too hot, I might use Max A/C with the rear windows cracked a bit to get it cooled down a bit before turning it back to normal A/C.



I agree that I wish Ford would have put a pollen filter in our 'Tracs. My wife's outback has one, and it gets quite nasty by 10,000 miles. Better to trap the stuff than to breathe it or get the insides of your vehicle dirty with it.