Heat pump water heaters are the most efficient type of electric water heater and are required under NAECA III for some applications. Heat pump water heaters are easy to install, but do require management of the condensation produced. Heat pump water heaters have built-in diagnostics to make troubleshooting easier. Most problems can be diagnosed with the built-in diagnostics and a multi-meter.
Some electric utilities require that installers be certified by the manufacturer in order to qualify for utility rebates. The certification test below meets current utility requirements.