A/C blows fog

[Philossifer]

Originally posted by Scrapla
After having my A/C on for about 5-10 minutes it will start to blow some mist like steam out of the vents and front defroster then goes away and comes back, you can smell moister when the A/C is on like the smell that somethings damp, kind of hard to explain but I hope you guys/gals can relate it still blows cold but not as cold as when I got it. I had my A/C compressor and that switch near the passanger fire wall with the shrader valve on it replaced about a year ago and all was fine until now, whats goin on?

Scrapla,
One of two things could be happening.

1) The evaporator condensate drain might be clogged. If so, water builds up near the evaporator and comes out of the vents as a cold mist. Straigten out a coat hanger and push it up into the drain tube to clear it of any obstructions. It's located on the passenger side (underneith the car) directly below the evaporator/heater box.

2) In very humid climates, it's normal. As the evaporator gets cold, it condenses most of the moisture out of the air passing over it but in very humid conditions, not all of the moisture is condensed. The white fog is a frozen mist in the humid air that's coming out of the vents.

The fact that you're getting the mist indicates that the evaporator is getting cold and the system is working properly.
Good luck,
Phil