This standard specifies the classification, basic specifications, technical requirements, test methods, inspection rules and signs, packaging, transportation and storage of combined air-conditioning units (units for short). This standard is applicable to those without cold and heat sources, the refrigerant is water, the heat medium is water or steam, and the functional section is used as a combination unit, which can complete functions such as air transportation, mixing, heating, cooling, dehumidification, humidification, filtration, and noise reduction. A unit with several processing functions. Refer to the units with brine or ethylene glycol as the refrigerant and electric heaters. This standard does not apply to units with built-in cooling and heating sources and direct evaporation coils.