A pump is a wheel on a stick. Some wheel, some stick! With today’s unlimited variable speed capabilities, the integration of hydraulics and electronics has resulted in a totally new industry. In the 1950s, the application of pumps in the HVAC field was pretty simple and standardized, as they were always constant speed. A number of unusual methods were developed for constant speed pumps to eliminate excess pump head, maintain constant flow in chiller evaporators and boilers, and to distribute the water in HVAC systems. Unfortunately, some of these design principles are being applied to variable speed pumps today with unnecessary complexity and energy loss. The need for proper application of variable speed pumps became a necessity.