Originally Posted by Big Budgie
If you have the airflow direction control on your heater/aircon control panel set to "Demist", ie directing the air onto the windscreen, the aircon compressor will automatically start. This is normal. If the air is set to go anywhere else, it should stay switched off until you put it on. There may be a fault with the airflow control which makes it come on in any position. Probably best to get it checked out.
Spot on, Thanks very much..
I have now set it to the midway position (50% up and 50% down) and guess what, the A/C does not come on every time I turn on the ignition.
Also, like you say, as soon as it is set to Demist, on comes the A/C !!
Sorts of makes sense really, as I guess you need dry air to demist.
I think it is working correctly now I understand its operation, so you have saved me a trip to the dealer.
Thanks for the explanation, I am glad I asked now as it was bugging me.
Cheers, and Happy Christmas.