This Standard specifies methods for measuring the performance of electric storage water heaters to produce domestic potable or non-potable hot water for household and similar use. The object is to state and define the principal performance characteristics of electric storage water heaters and to describe the test methods for measuring these characteristics. NOTE 1 – This standard does not apply to; - storage water heaters that use electricity as a secondary source of heating the water; - storage water heaters that do not use a tank to storage hot water; - electric storage water heaters that do not meet the minimum (or maximum) output performance of the smallest (or biggest) load profile, as defined in Table 4. - water-heaters without thermal insulation NOTE 2 – This standard does not specify safety requirements. For safety requirements see IEC 60335-1 in conjunction with IEC 60335-2-21.