Water-cooled compressors are well known for providing reliable starting air for marine diesel on small, medium-sized and large ships and engine based power station. This type of compressors is the best choice if the engine room temperature is very high. The water for the cooling system of these compressors are supplied by centrifugal pumps and has radiator system for cooling the hot water that comes out from the compressor. Air production could be hampered either by operators wrong manual operation of centrifugal pumps or heat exchanger system which eventually affect engine operation also. The aim of this paper is to describe the methods of the PLC controlled system to maximize the process efficiency, avoiding the operator alienation and keeps it safe trough automated system with PLC logic.