This video compares the Bradford White Aerotherm, A. O. Smith Voltex, and Steibel Eltron Accelera heat pump water heaters under long term real world conditions in a cold climate.

Deep dive into the Bradford White Aerotherm issues:    • Why I think the Bradford White Aeroth...  

All the nerdy details about Heat Pump Water Heaters from the US Department of Energy: https://www.nrel.gov/docs/fy13osti/58...