Fans blow air over your skin, which promotes moisture evaporation. Evaporation is an endothermic process, meaning the moisture absorbs heat from its surroundings as it turns into vapor.
Something has gone wrong in or around the heater core — a small radiator through which a fan blows air into the cabin to keep everyone toasty. Related: Tips for Starting Your Car in Subzero ...
Essentially, it has a similar effect as any of the best fans you'd have at home. Fans cool us by blowing air over our skin, ...