Air Recirculation Question

Mine actually blows more air volume at max setting. You can really feel it. Could be lower restriction from the in-cab vent intake.

I(t is a common mis-conception that "Fan Speed Kicks up a bit" It does not, the sound does because you are hearing air sucked into the re-circulate port.

The 80/20 mix comes from, I Think a Chevrolet owner's manual.. Or my Workhorse (Evans) not sure.

My Dodge car is either or.. and independent of all other controls, NO max setting since the recirculate control is the ONLY difference between Normal and Max.

I don't do Fords

My 2001 owner's manual say use "MAX A/C" for recirculating. Fan speed kicks up a bit too so turn down the fan if it is too much. Same cooling BTU either way.

At the time I understood it was only about 80% recirculated. Same for normal A/C is only 80% fresh air.

Normal A/C is having mostly fresh air according to Ford. What exactly do you do you expect to be different?

wa8yxm wrote:
Normal A/C geneally recirculates about 80% on most vehicles, the other 20% is "Fresh" air drawn from outside.

For the Ford chassis system it operates in full recirculation, or full outside there is no in between. In fact I know of no chassis system that operates in a partial recirc mode, unless it has advanced controls such as an AQS, Humidity Sensor, or Auto. And that's my job so.....

Normal A/C geneally recirculates about 80% on most vehicles, the other 20% is "Fresh" air drawn from outside.

The ONLY difference between NORMAL air and MAX depends on the control system
But MAX is 100% recirculated.

IN SOME cases you must be on high fan for MAX to be selected, in other cases you can still turn the fan down.. On my system I can still select a slower fan speed.

But MAX is 100% recirculated, that's the only real difference.

IT SOUNDS like air is rushing faster because you are hearing the INTAKE not the outlets.

It can only do recirculation while in MAX A/C mode. Recirculation should mainly be used when cooling the vehicle and the A/C system is operating, otherwise it can and does cause excessive window fogging.