India being a tropical country has high temperature and humidity during summer. It is expensive to maintain comfort conditions through air-conditioning devices; however, scarcity of electricity is another problem. Therefore, desert coolers are being used in most of the areas of the country, which consume comparatively less amount of electricity. However, it is not fully efficient for the humidity as well as for cooling. This paper describes the methods of modifying and designing a desert cooler to make it multipurpose. This multipurpose desert cooler as the name suggests is the modification of desert cooler which not only works as a cooler but also as a water cooler, dehumidifier and storage box through its accessories. An analysis and performance measures is done for comparison purpose. It is observed that the modified cooler lowers the room temperature up to 21 °C which is 6 °C less than the conventional desert cooler. The temperature of water inside the water cooler decreases up to 15 °C. It also reduces moisture content of the out coming air to some extent. The storage box temperature is maintained at 18 °C, which is suitable for storing perishable food items. This multipurpose desert cooler can be used in houses, banks, offices, auditoriums, etc. Keywords: Conventional desert cooler (CDC), modified desert cooler (MDC), conventional pot (CP), modified pot (MP)Cite this Article Tomar Anil Singh, Singh Swadesh Pratap, Singh Abhay Pratap, et al. Multipurpose desert cooler: A diagnostic approach to enhance the performance. Journal of Refrigeration, Air Conditioning, Heating and Ventilation. 2015; 2(3): 1–4p.