Mine is also a 2006 XC70 D5 that has difficulty demisting first thing in the morning. Same as you, no coolant leaks from heater matrix,clean pollen filter no blockages to vents etc and takes substantial amount of time to clear. I suspect that on a cool,damp night moisture that previously condensed in the heating/cooling system doesn't evaporate and so you end up blasting damp air until it dries out.
It might be just a placebo effect but it seems to help if I either don't use the aircon or if I've had the ventilation system on auto and the air con has been working I try to remember to turn the aircon off for the last mile or so before getting home in the belief that it will dry out. Seems to work (a bit) but would it have been the same if I hadn't done that?
John
|