Peter Zak, P.E., Principal, Graef Anhalt Schloemer & Associates, Milwaukee, Wis.

Priming Pumping Possibilities

As long as HVAC systems use water as a means of heat transfer, engineers will continue to design variable flow systems to maximize efficiency. There are numerous combinations currently in use. Most common are primary-secondary, variable primary and variable flow with distributed pumping. Each system provides variable flow and a degree of system efficiency.