HVAC Electrification: Heat Pump Product Capabilities

This study evaluated the capabilities and real-world performance of heat pumps used for space heating and cooling in nonresidential buildings to support future California Title 24, Part 6 code development and market adoption. The research combined a review of more than 50 product lines from 21 manufacturers, 29 stakeholder interviews, and field monitoring at 11 California buildings. Results indicate that part-load operation, compressor turndown, hydronic pumping, supply-water temperatures, heat recovery configuration, and control behavior strongly influence system performance. The study identifies code-readiness opportunities related to compressor turndown, water-temperature reset, heat recovery sizing, pumping efficiency and controls, crankcase heater control, and refrigerant global warming potential intensity. It also recommends improved manufacturer performance reporting, controls documentation, BAS integration, and additional research on defrost, variable-speed compressors, peak-demand management, low-GWP refrigerants, and monitoring points.