Local pumping system
Notes that in a hydronic piping system, centrifugal pumps provide the primary force to distribute and recirculate process water by overcoming water pressure drops and power losses in the system. All distributing pumps are centrally located with balancing valves and control valves installed at cooling coils, heating coils and heat exchangers to restrict and regulate water flow by creating water pressure drops and power losses across the valves. In a system with a large number of balancing valves and control valves, total water power and energy losses across the valves can be significant. States this wasted pump power and energy would be eliminated if the balancing valves and control valves were removed from the pumping system. Introduces a pumping system where pumps are locally located at the coils. The local pumps circulate and regulate water through the cooling coils, heating coils and heat exchangers without balancing valves and control valves. Citation: ASHRAE Journal, vol. 42, no. 9, September 2000