USE OF COMPOSITION AS REFRIGERANT IN DEVICE, DEVICE, AND REFRIGERATION CYCLE DEVICE

To provide a use of a composition as a refrigerant in device in which propagation of refrigerant disproportionation reaction is suppressed.SOLUTION: Provided is a use of a composition that contains one or two or more selected from the group consisting of ethylene-based fluoroolefin, 2,3,3,3-tetrafluoropropene (HFO-1234yf), and 1,3,3,3-tetrafluoropropene (HFO-1234ze), as a refrigerant in a compressor (21) having 1st to 5th heat-absorbing units (51, 52, 53, 54, 55) that constitutes 1st to 9th refrigerant pipes (11 to 19), a gas side refrigerant connection pipe (5) and a liquid side refrigerant connection pipe (6) as well as a refrigerant circuit (10) and in which the heat capacity of the part whose melting point is 1000°C or higher is 6.5 J/K or more.SELECTED DRAWING: Figure 3 【課題】冷媒の不均化反応の伝播を抑制する。【解決手段】エチレン系のフルオロオレフィン、２，３，３，３－テトラフルオロプロペン（ＨＦＯ－１２３４ｙｆ）、および、１，３，３，３－テトラフルオロプロペン（ＨＦＯ－１２３４ｚｅ）からなる群より選択される１種または２種以上を含む組成物の、第１～第９冷媒配管（１１～１９）とガス側冷媒連絡配管（５）と液側冷媒連絡配管（６）とともに冷媒回路（１０）を構成し、融点が１０００℃以上である部分の熱容量が６．５Ｊ／Ｋ以上である第１～第５吸熱部（５１、５２、５３、５４、５５）を有する圧縮機（２１）における冷媒としての使用。【選択図】図３