Steamy Windows??

I have a 4 year old V40 with electronic climate control which as far as I
can tell is working ok with the exception that the windows often mist up for
a few seconds when I first start the car. Unless the weather is really cold
it clears pretty quick but can anyone tell me if this is normal or is there
an underlying problem?

FYI: I don't drive with the recirculate on very much and the recirc does
seem to open/close properly.

Cheers.
Roger.

 

There seems to be some water in your air system after you park the car.
Does your air conditioner run all the time? In a humid climate, that would
do it. Perhaps the water drain is slightly blocked.

 

Marvin,

Yes I run it all the time. What are the implications?
I do get water under the car but I suppose the drain could be partially
blocked. Any idea where it is?

I'm getting the Haynes Manual for Christmas

Cheers.
Roger.

 

Air conditioner compressors last much longer is left on year around.
They are turned on anyway for air conditioning and defogging.

To prevent fogging, it is necessary to switch to outside air when the
outside temperature is low like below 60F or 15C. Cold outside air has
a lower absolute humidity, even when it is raining, snowing, or foggy.

To prevent fogging in warm or hot weather, above 80F or 25C, you need to
close the outside air vents since in many climates this air has a very
high absolute humidity.

In between it shouldn't matter. It may be necessary to turn on the AC
and use the defogging position to counteract moisture retained in the
system when shut off and not completely drained out.

A blocked drain will result in horrible fogging problems that can't be
overcome unless the AC is turned off completely. A leaking water line
in the heater box will give the same effect but will also leave a sweet
smell from the antifreeze.

 

Maybe so, I dunno, never had a compressor fail before. I do know that it
cuts my fuel economy by 10-15% when the AC is on. I do try to run it for a
few minutes every few days, often gets used in the morning to defog the
windows anyway.