When the thermostat is set to auto and the temperature of the interior reaches the temp you set it at, shouldn't the system begin to regulate the temp by providing hot or cold air to keep the interior at the desired temp.

I find myselft getting hot or cold and I keep adjusting the temp. When I took it to the dealer they said that you shouldn't keep it on auto and lower the fan.

 

The Auto function itself will regulate fan speed based on the temp you set. The greater the difference between the current temp inside the car and the temp you set, the more fan will be used to bring the temp to the desired temp as fast as possible. As it reaches the desired temp, the fan will gradually decrease until it is brought down to minimum. At that point, it will continue to regulate both the blown air temp and the amount (fan) of air to maintain the desired temp.

 

I'm on auto almost all the time. If I'm warm or cold I just adjust my temp a bit. I've been very happy with the system. The only time I'm not on auto is if I get stuck behind a deisel or I'm in a tunnel, and that's just because I put on recirc to avoid the fumes.

 

the auto system is ingenious, everyone that gets into my G and notices that is impressed, because when you think about it, its like the a/c system in homes...

 

I usually use it for cold temps only (summer time). During the winter, I don't see a reason to run the A/C when I can just crank up the heat that comes off the engine.

 

That's one thing I miss about my Volvo S60. It had sensors to detect odors and contaminents, and would automatically switch over to recirc. Worked very well. It would also periodically switch from recirc to fresh air to maintain optimal interior air quality. Very cool feature.

I do find that I have to adjust my G temp down over time, that it tends to get a bit warmer over time than I would expect from the setpoint.

 

You should run the AC for 15-20 minutes each week. It's mechanical and anything mechanical needs to be moved once in a while.

 

I use it whenever the inside gets foggy...

 

I'm pretty sure that the G has a variable displacement compressor... I know the old Q45s did. This means that they were able to run the A/C compressor at a lower capicity (less engine load) and still use it to regulate humidity. I leave mine on "Auto" all year, and have had very good luck with the Q compressor (120K+ on one compressor) vs. the typical results.

Heath

 

I may be incorrect, but I thought that AC systems won't turn on below a certain temperature, around 50 degrees. so turning it on in the winter won't actually do anything.

 

If you use defrost, it will use the compressor to dehumidify the air. There is a temperature cutoff, but it is way lower than 50. More like 15 degrees or something around there, according to the manual.