I read a post on here a while ago about somebody noticing that their A/C compressor was cycling on and off without the A/C even turned on if they had the airflow selected to blow to the floor.

Well.....now that it has gotten cold and I have had to use the heat, I've noticed this as well and it is quite annoying.

Why the hell do they have the system designed to do this? Does anybody know? I've had cars before where if the system "thought" it needed to cycle the compressor for some reason (like to dry the air for the defroster setting) and lit the light up showing it was on, but it would allow you to turn it off. If I wanted dryer air when I had just the floor heat on, I would fire up the A/C compressor myself with the switch.

I'm about ready to just disconnect the wiring harness at the compressor until it gets warm enough to need the A/C again. Why rob a little bit of power and consume more fuel to warm my feet. I've noticed that it does not cycle if you have the selector on both dash vents and floor, or just dash vents. I don't know about you guys, but I don't like hot air blasting me in the face while I'm driving, so I want to use just the floor air for heat.

Seriously annoyed by this!!!

 

I find this annoying and disconcerting as well. I can't understand why... it's bad enough cycling on defrost, but at least that serves some practical purpose.

 

Forgive me for stating the obvious, but until someone figures out something better you can close the round vents and re-direct the center ones...don't know what else to suggest.

 

Umm, this only happens with the vents directed to floor only, or to defrost. Not with forward-facing alone or forward-facing/floor combos. So, your suggestion will not help.

 

The times when the AC unit is engaged regardless of the "AC" button is explained in the manual. Well at least *when* the AC is forced on is explained, but not neccessarily why it's forced on. My guess would be to control humidity, especially when trying to defrost the windshield. The AC systems do a very good job of removing humidity in the air and I can imagine this is beneficial with the heat on and the windows closed. Probably some idiot filed a lawsuit somewhere because the inside of their car fogged up with the heater on, so now we all get to have the AC on when the floor heat is selected.

Simon.

 

Well, then I guess he would need to keep his head out of the footwell while driving, because he said he didn't like air blasting him in the face...
My suggestion was to close the dash vents while the air is directed to both dash and floor to achieve that effect (more or less).