Circulator Pump Controls Field Study

In 2024, PG&E’s Code Readiness Program research team initiated a research project for circulator pumps to identify and estimate energy savings and costs for different types of controls for circulator pumps in multifamily and non-residential buildings. The findings from this research will be used to guide potential updates to the 2028 Title 24 building energy efficiency standards regarding circulator pumps in central DHW and SHW systems. DHW and SHW systems are the second-largest energy end use in U.S. buildings. Recirculation systems are commonly installed to ensure hot water is delivered to the end user without long waits or significant water waste and can increase the energy needed to heat the water. By adding controls to circulator pumps, the amount of energy needed to heat the water is reduced. The team recruited five field sites, four multifamily sites and one non-residential hotel site that are located within California and have a recirculation system. Monitoring equipment was installed at each site to determine the energy consumption of each control method. This report presents the field site monitoring results and key findings from this research.