Circulator pumps are small, single-stage, overhung, in-line style rotodynamic pumps. They are supported in-line by the system piping and rotating assemblies that must be horizontally mounted. The pumps are small but typically have long run hours. Most circulator pumps are fractional horse power and less than 3.75 kW (5 hp). Common applications are hydronic heating and hot water recirculation. Pumps now on the market with electronically commutated motors and integrated variable speed control offer 50% or greater savings over standard pumps. In hydronic heating applications, energy conservation is due to improved motor efficiency and motor speed controls. For potable hot water recirculation, hot water is circulated from the water heater, through the hot water piping, and back to the water heater. Efficient circulator pumps save energy in these systems by reducing pump run time and water heating energy.
Current Stage: Approved for Implementation. See BPA Energy Efficiency Implementation Manual and Regional Technical Forum Measure Page for measure and program details.