The propagation of a disproportionation reaction of a refrigerant is suppressed. Disclosed is a method that uses a composition as a refrigerant in a compressor, in which the composition includes one or more compounds selected from the group of ethylene-based fluoroolefins, 2,3,3,3-tetrafluoropropene, and 1,3,3,3-tetrafluoropropene, the compressor forms a refrigerant circuit together with first to ninth refrigerant pipes, a gas-side refrigerant communication pipe, and a liquid-side refrigerant communication pipe, and the compressor includes first to fifth heat absorbing portions in each of which a heat capacity of a portion with a melting point greater than or equal to 1,000° C. is greater than or equal to 6.5 J/K.

The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises about 49% by weight difluoromethane (HFC-32), about 11.5% by weight pentafluoroethane (HFC-125), and about 39.5% by weight trifluoroiodomethane (CF.sub.3I), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises an alkylated naphthalene and optionally but preferably an acid depleting moiety.

To provide a composition for a hat cycle system which comprises a working fluid containing 1,1,2-trifluoroethylene, having cycle performance sufficient as an alternative to R410A while suppressing influence over global warming, and a heat cycle system employing the composition.

A composition for a heat cycle system, which comprises a working fluid for heat cycle containing 1,1,2-trifluoroethylene, CF.sub.3I and at least one compound selected from a hydrofluorocarbon, a hydrofluoroolefin other than 1,1,2-trifluoroethylene and a hydrocarbon, and having a temperature glide of at most 7° C., and a heat cycle system employing the composition for a heat cycle system.

Disclosed herein is a method for producing cooling comprising evaporating a liquid refrigerant comprising (a) E-CF.sub.3CH═CHF and (b) at least one tetrafluoroethane of the formula C.sub.2H.sub.2F.sub.4; provided that the weight ratio of E-CF.sub.3CH═CHF to the total amount of E-CF.sub.3CH═CHF and C.sub.2H.sub.2F.sub.4 is from about 0.05 to 0.99, in an evaporator, thereby producing a refrigerant vapor. Also disclosed herein is a method for replacing HCFC-124 or HFC-134a refrigerant in a chiller designed for said refrigerant comprising providing a replacement refrigerant composition comprising (a) E-CF.sub.3CH═CHF and (b) at least one tetrafluoroethane of the formula C.sub.2H.sub.2F.sub.4; provided that the weight ratio of E-CF.sub.3CH═CHF to the total amount of E-CF.sub.3CH═CHF and C.sub.2H.sub.2F.sub.4 is from about 0.05 to 0.99. Also disclosed herein is a chiller apparatus for cooling, said apparatus containing a working fluid comprising a refrigerant comprising (a) E-CF.sub.3CH═CHF and (b) at least one tetrafluoroethane of the formula C.sub.2H.sub.2F.sub.4; provided that the weight ratio of E-CF.sub.3CH═CHF to the total amount of E-CF.sub.3CH═CHF and C.sub.2H.sub.2F.sub.4 is from about 0.05 to 0.99.

The present invention provides a refrigerating machine oil comprising, as a base oil, at least one oxygen-containing oil having a carbon/oxygen molar ratio of 2.5 or more and 5.8 or less, wherein the refrigerating machine oil is used with a refrigerant comprising 15% by mass or more of difluoromethane, 15% by mass or more of pentafluoroethane, 15% by mass or more of 2,3,3,3-tetrafluoropropene and 15% by mass or more of 1,1,1,2-tetrafluoroethane based on the total amount of the refrigerant.

A refrigeration cycle apparatus according to the present invention includes a refrigerant circuit formed by connecting, by pipes, a compressor configured to compress a refrigerant sucked into the compressor and discharge the refrigerant, a condenser configured to cause the refrigerant to reject heat and condense the refrigerant, an electronic expansion valve configured to reduce a pressure of the condensed refrigerant, and an evaporator configured to cause the refrigerant to remove heat and evaporate the refrigerant, in which the refrigerant is a refrigerant mixture including R32 and HFO-1123, and in the refrigerant mixture, R32 is greater than HFO-1123 in mass %.

The present invention provides a refrigerating machine oil comprising: a base oil comprising an ester of a polyhydric alcohol and a fatty acid comprising 20 to 100% by mol of a branched fatty acid having 4 to 9 carbon atoms; and 0.2 to 0.5% by mass of a phenol-based antioxidant based on a total amount of the refrigerating machine oil, and the refrigerating machine oil being used with trifluoroethylene refrigerant.

An object of the present invention is to provide a refrigerant composition having a reduced amount of comprehensive environmental load, in which the refrigerant composition has low GWP (direct impact on global warming is low), and has good energy efficiency (indirect impact on global warming is low) when used in a device.

The present invention provides a refrigerant composition comprising 30 to 50 mass % of difluoromethane (HFC32) and 70 to 50 mass % of 2,3,3,3-tetrafluoropropene (HFO1234yf).

Compositions, methods and systems which comprise or utilize a multi-component mixture comprising: (a) from about 10% to about 35% by weight of HFC-32; (b) from about 10% to about 35% by weight of HFC-125; (c) from about 20% to about 50% by weight of HFO-1234ze, HFO-1234yf and combinations of these; (d) from about 15% to about 35% by weight of HFC-134a; and optionally (e) up to about 10% by weight of CF3I and up to about 5% by weight of HFCO-1233ze, with the weight percent being based on the total of the components (a)-(e) in the composition.

A composition for a heat cycle system having less influence over the ozone layer, a low global warming potential, and excellent stability and durability is provided. A heat cycle system using the composition is also provided. The composition contains a working fluid and a phosphoric acid ester. The working fluid contains trifluoroethylene and difluoromethane. An interaction distance (Ra) between the working fluid and the phosphoric acid ester as determined from the Hansen solubility parameters is at most 15.