This Standard specifies the test procedures used to determine methods of determining the energy factor (EF) or standby loss, as applicable, for electric storage tank water heaters and heat pump water heaters.
This Standard specifies the minimum energy efficiency levels for electric storage tank water heaters and heat pump water heaters.
This Standard applies to
(a) electric storage tank water heaters with
(i)volumes of 50 to 454 L (13 to 120 US gal); and
(ii)electrical heaters with power inputs up to 12 kW; and
(b) heat pump water heaters that have
(i)a maximum current rating of 24 A;
(ii)a single phase maximum voltage of 250 V; and
(iii)ancillary equipment necessary for the device to function.
This Standard does not apply to high temperature water heaters.
The tests contained in this Standard are not intended to represent actual efficiencies realized in the field. Instead, these tests provide a standardized method of comparing performance.
This Standard is written in SI units. The values in parentheses are for information only. The SI values have been calculated from the imperial measurements found in DOE publication 10 CFR Part 430.