Distributed pumping offers a great advantage on systems where there is a great difference in distribution friction between zones or buildings. Examples given schematically are an airport, in which secondary pumps were eliminated and building motors from 50 hp to 200 hp were installed in lieu of secondary pumps, and a regional college campus, in which a sizeable reduction in overall pumping requirements was achieved by replacing the secondary pumps with building pumps. Distributed pumping eliminates building crossover bridges, return temperature control valves, and in many cases, the need for balance valves on the heating or cooling coils. The overall efficiency of these systems is said to be far above those utilising primary/secondary/tertiary systems, or systems with pressure control valves, crossover bridges or balanced valves on all coils.

KEYWORDS: water pumps, pumps, controls, chilled water supply, hot water supply, calculating, airports, universities, water flow, cooling, heating.