Besides high efficiency, the most important factors are service life, availability and operational reliability. During the past three decades, increasing power station unit output resulted in a considerable rise in feed pump energy consumption. Additionally although most of these plants were designed for base load operation, the feed pumps were subject to cyclic operation during their lifetimes. To solve feed pump problems in existing power stations is a highly complex process. Experience shows that while a pump in one power station operates satisfactory, whereas a machine of the same design causes permanent trouble in another. Power station boiler feed pumps operate only as well as their design is matched to all system requirements. Thus, knowledge of system parameters and operating conditions is the major prerequisite to analyze pump problems. Simply replacing a non-running pump by a new one, even of a different make, is not always the best technical and economic solution.