Sound silly, but can someone tell me the difference in the choices on the A/C dial in my truck?

Max may be closed vents to recirculate the interior air, but is that what it does?

I know the choice with the Hi/Lo output turns on the air, but is the only difference between that and "AC" just that it discharges to both the upper and lower output vents and AC only uses the upper?

Has anyone put a compressor on/off switch in the loop to allow using Max to cool the truck down and keep the recirculating mode on to just blow the internally cooled air for a period?

I want to understand this so I can watch the clutch and know when it should be engaging (I will only watch while the truck is parked ).

If I have the air on, can I change the temp control to keep the clutch from engaging more often to save on some fuel?

Thanks.

 

The difference between Max AC & AC is recirc for Max versus fresh air on regular AC....as for turning towards a warmer setting w/ AC on the compressor will still run. As for forcing it to switch on/off alot by any means (making a "switch"), this would most likely just overheat and damage the clutch and also prematurely cause your compressor to fail......they don't like being short-cycled.

 

Also running the a/c doesn't hurt the fuel milage.

 

My a/c seems to be on all the time, is there a common problem with some part of the system in the super duties?

 

Check this link.

SpringerPop's Compressor Clutch Air Gap

 

Im almost certain it will run in every setting except for Floor only vents

 

A/C runs in most modes to de-humidify the air.

It especially helps when in defrost mode to de-fog the inside of the windshield.

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