How to prevent the fog on windows with AC ON

 Hi All,

  I don't know whether this is a common issue or not  but it was observed in two cars.While driving Tata Nano I observed that a layer of fog forms on the front glass sheild for which I was keeping the AC at minimum and wiping it with hand or cloth.The same I observed for Hyundai I10.Both of them were new cars at the time of observation.Is it due to humidity? How to tackle it?

   I observed another thing for my I10,that there was some condensation on roof top outside especially evenings and nights.I don't know whether it was same for Nano or not?I thought it was due to the high humidity outside but whether it indicates some problem with roof insulations.There was no problem with AC and cooling.

 Third observation was the cold air from AC turns into normal air during some steep or moderate curves.After 10 to 15 min,it became normal.It was observed 1 or 2 times only on long drive while at higher speeds ( 90 to 100 kmph).The same I observed once on my Hyundai Elantra 2.0Lt AT car and without any other issues.

  What happened and do I have to get them checked.

Yes! it is because of Humid. Also it is not receommended to use hand to wipe front glass. Use quality news papper and wipe wind shield clearly. then use the AC Balanced. You wont get fog.

To avoid it, move the AC control to Defogger mode and Air circulation mode. Switch on the AC (COLD) and keep the blower level to 4. The fog formation will go off in seconds

Thanks for the reply.I will check it.

I have read some where to use the hair dryer to dry the interior of the car as the seat covers and the roof coating, this result in less fog formation. As I do not try it because I don't have the hair dryer, but if you have it please try it and please reply that it works or not.

Heater & Defogging: Always use the heater with the air conditioner's toggle button turned on 'Fresh air' mode. Set air intake control and air flow control to a well ventilated position and the temperature control function to a comfortably warm position. When the car is fogged from inside, the AC can be used for increased defogging action

Source: Hyundai Website

What I do in such condition: Turn on the A/C at fan speed 1, turn the air flow upward on the windshield and you will see fogging is gone in less than a minute (time may vary depnding upon the fogging there on the glass), make sure not to continuous blow air on the windshield it will creat fogging from outside the glass and will need to use wiper to get rid of that ;-)