this invention relates to an air conditioning apparatus and in particular to one including a compressor , an evaporator , a cooling fan , a low pressure pipe , a high pressure pipe , a radiator , a cooling motor , and a condenser . the apparatus is characterized in that the heat exchanging efficiency between the cooling water and the refrigerant is highly enhanced , thereby intensifying the cooling effect and increasing the temperature of the cooling water flowing out of the apparatus to an acceptable degree for residential hot water . further the radiator may be separated from the apparatus thus making it suitable for use in varied applications .