IEC 63159-1:2021的本条款适用，以下情况除外。 补充: 本文件适用于家用或类似用途的开放式单点使用瞬时电热水器，用于淋浴，无需下游混合。 本文件仅规定了能源效率评估试验。 本文件不适用于本系列标准其他部分所涵盖的瞬时电热水器。

This clause of IEC 63159-1:2021 is applicable except as follows. Addition: This document applies to open outlet, single point-of-use, electric instantaneous water heaters intended for household or similar use, for showering purposes without downstream mixing. This document only specifies tests for the assessment of energy efficiency. This document does not apply to electrical instantaneous water heaters covered by other parts of this series of standards.