The above interpretation about the relationship between the odor production, intensity and evaporator operation time and the amount of air condensed on the surface of evaporator is considerably related to the fact that a lot of consumer complaints related to their air-conditioning system mainly happen in spring and autumn. In fact, relative humidity is very high in summer (annual average: 80%,Korea Meteorological Administration, 2006) and the users normally use their air conditioners for a long time, which makes less odor productions, faint odor intensity, and characteristics. This fact makes the odor complaints few in summer. Conversely, relative humidity is relatively lower in Spring and Autumn (annual average: 50–60%, Koreameteorological administration, 2006) than summer and users normally use their air conditioners for a short time to make it cool temporally or to remove the moisture from their windshield, which makes high odor productions and strong odor intensity and characteristics. This fact induces many consumer complaints in spring and autumn.