<p>This paper discusses the reliability and profit analysis of a single unit centrifugal pumping machine having higher Maintenance and Replacement Policy operated by a technician. Mechanical faults are classified as soft, hard and neglected fault based on repair time and cost implications. Soft errors cause system production time, while hard errors cause complete machine failure and neglected fault is either convert soft fault or convert hard faults. After the failure, the technician checks the correction of the error before taking the necessary action. Sometimes various faults are checks by online methods. Various estimates of system performance are obtained using Semi-Markov methods and regenerative point techniques. Graphical analysis is used to analyse the process, resulting in a reliable understanding of the costs involved. This study provides valuable insight into improving the reliability and cost of single unit centrifugal pumps<b>.</b></p>