This document specifies the terms and definitions, requirements, and test methods for the water heating/cooling system of cardiopulmonary bypass systems. This document applies to the water heating/cooling system of cardiopulmonary bypass systems (hereinafter referred to as the 'heater-cooler device'), which serves as the driving device that provides heated water, cooled water, and raw water to the heat exchanger in the cardiopulmonary bypass blood heat exchange system, for temperature regulation during cardiopulmonary bypass perfusion in medical institutions. This document applies to: —Heater-cooler device for extracorporeal membrane oxygenation (ECMO)(hereinafter referred to as the 'ECMO heater-cooler device'); and —Heater-cooler device for cardiopulmonary bypass (CPB) (hereinafter referred to as the 'CPB heater-cooler device').