Heat Pump Water Heaters for Single-Family Homes (Building America Solution Center)
U.S. Department of Energy / Pacific Northwest National Laboratory
DOE/PNNL technical guide to heat pump water heaters: UEF and first-hour-rating selection, minimum air-volume and ducting requirements, condensate drainage, 240V circuit sizing, noise placement, and annotated right-versus-wrong installation photographs with code citations.
More resources on Water Heaters
familyhandyman.com
Family Handyman is a DIY home-improvement site offering step-by-step guides, tips, and projects for home wiring basics and electrical safety. Content includes tutorials on wiring outlets and switches, circuits and panels, tool recommendations, and troubleshooting advice.
The Water Heater Workbook: A Hands-On Guide to Water Heaters
Weingarten's 166-page field manual on tank anatomy, why heaters fail, anode and dip-tube replacement, sediment control, gas and electric control diagnosis, and sizing. Illustrated throughout; widely cited by plumbers as the reference on extending heater life.
Water Heater Rescue
An independent 250-page reference on tank water heaters, covering anode rods, sediment flushing, dip tubes, T&P valves, smelly-water chemistry, and step-by-step troubleshooting for gas and electric units. Online since 1995, maintained by the authors of the Water Heater Workbook.