Go breathe on a window or mirror. See the fog? That's condensed moisture from your breath.Sylvain said:Hi, just got my Odyssey 2002 EX last night
Why would the A/C start when I switch to 'Defrost'Normally (ie, in my other cars), when I used Defrost, it's to bring HOT air to the windshield to melt the thin ice/frost on it. Not to freeze it!
Thanks
That very same moisture coming from the occupants of the car will condense on the inside of the cold windows, which fogs them up--and you can't see through the fog. You need to get rid of the moisture.
A little known fact: the air conditioner in a car isn't meant to give cool air so much as it is to give DRY air. Dry air allows your body's natural cooling mechanism, sweat, to work.
Dry air also gives room for the natural moisture from your breath to evaporate. So, to get rid of the moisture that's condensing on the windows, you need to evaporate it with warm air and that warm air has to be dry. Moist warm air won't evaporate the moisture from the windows. Moist warm air directed at the windows will do nothing but put more condensation onto the inside of the windows, and cause *more* problems seeing through them.
So you need the air conditioner year-round, because your body is 97% water and all that moisture causes problems whether it's summer (you need to get rid of the sweat to feel comfortable) or winter (you need to keep the moisture from your breath from condensing onto the cold windows).
Air that's been through the A/C doesn't have to be cold. Just heat it back up again with the heater by turning the heat up.
Moisture is everywhere about a human being, and enclosed spaces are uncomfortable for that reason. (Ever pull the covers over your head in bed and try to stay that way for any length of time? Uncomfortable, isn't it? If you had air conditioned--dry--air circulating under the covers, you wouldn't be uncomfortable. Even better if that air was first dried and then heated to a comfortable temperature.)
