Application Guidance: Heat Pump Water Heaters

Heat pump water heaters (HPWHs) can provide domestic hot water in multifamily and light commercial buildings, and in some configurations can also support hydronic space heating. System design requires consultation with a licensed contractor or engineer, as installation often involves integration with both plumbing and heating distribution systems.

Sizing is driven primarily by peak hot water loads. Engineers typically use demand profiles based on occupancy, fixture counts, and usage schedules to determine the required capacity. Normalized sizing approaches, such as heating capacity per square foot of floor area, can provide a useful starting point but should be confirmed against measured or modeled demand for each application.