This paper attempts a preliminary assessment of indoor conditions and thermal comfort in a room coupled with direct evaporative cooler in four different climatic zones of India. A room in a building has been simulated to obtain diurnal hourly values of room air dry bulb temperature and relative humidity for the summer months of March, April, May and June in selected locations in (i) hot and dry, (ii) composite, (iii) warm and humid, and (iv) moderate climatic zones.