As the main energy-consuming equipment of the centralized air-conditioning system

the improvement of the energy efficiency of water chiller (heat pump) units has a significant role in promoting the realization of the "dual carbon" target. GB/T 18430

as a basic standard for plumbing units

is nearing the end of its revision

and the accompanying energy efficiency standards GB19577–2015 need to be revised and upgraded accordingly. In this study

the assessment method of comfort-type water chiller (heat pump) units in GB/T 18430 is analyzed and compared with those of the corresponding U.S. and European standards. A theoretical model of water-cooled water chiller (heat pump) units is constructed such that the limited value levels specified in the energy efficiency standards of China

the U.S.

and Europe are converted into the same index for comparison. The IPLV entry limit values of China's water-cooled units

after increases of 5.4% and 25.2%

can match the energy efficiency levels of Path A and Path B of the American standard

respectively

and align with the European standards after a 13.4% increase; the energy efficiency limit values of air-cooled units can be basically on par with the European energy efficiency standards after increasing by 25.4%. This work provides a reference for the subsequent revision of the energy efficiency standard GB19577—2015.