A refrigeration cycle apparatus that is able to suppress a decrease in capacity when a refrigerant that contains at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10) in which a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), a liquid-side connection pipe (6), an indoor heat exchanger (31), and a gas-side connection pipe (5) are connected, a refrigerant containing at least 1,2-difluoroethylene is used, a pipe outer diameter of the liquid-side connection pipe (6) and a pipe outer diameter of the gas-side connection pipe (5) each are D.sub.0/8 inches (where, D.sub.0- inches is a pipe outer diameter of a connection pipe when refrigerant R32 is used), a range of the D.sub.0 of the liquid-side connection pipe (6) is 2D.sub.04, and a range of the D.sub.0 of the gas-side connection pipe (5) is 3D.sub.08.

The present invention relates to a composition comprising HFO-1234yf, or trans-HFO-1234ze, or a mixture thereof; HFC-32; and HFC-152a, HFO-1243zf, or a mixture thereof, wherein said composition is selected from the group consisting of: (I) a first composition, wherein said HFO-1234yf or trans-HFO-1234ze or a mixture thereof is at least 56 weight percent of said first composition; (II) a second composition, wherein said HFC-32 is at most 29 weight percent of said second composition; (III) a third composition, wherein said HFC-152a is at least 56 weight percent said third composition; (IV) a fourth composition, wherein said HFC-32 is at least 56 weight percent of said fourth composition; (V) a fifth composition comprising trans-HFO-1234ze, HFC-32, and HFC-152a, HFO-1243zf, or a mixture thereof; and (VI) a sixth composition, wherein said HFO-1243zf or mixture thereof with HFC-152a is at most 20 weight percent of said sixth composition.

In accordance with the present invention refrigerant compositions are disclosed. The compositions comprise HFC-32, HFC-125, HFO-1234yf, HFC-134a, and CO.sub.2. The refrigerant compositions are useful in processes to produce cooling and heating, in methods for replacing refrigerant R-410A or R-22, and in refrigeration, air conditioning or heat pump systems. These inventive compositions are non-flammable and match cooling performance for R-22 and R-410A within 15%. Additionally, these compositions may serve as replacements for R-404A, R-507, R407A, R407C and/or R-407F in refrigeration, air conditioning or heat pump systems. The compositions as described herein have unexpected flammability properties.

In accordance with the present invention refrigerant compositions are disclosed. The compositions comprise HFC-32, HFC-125, HFO-1234yf, HFC-134a, and CO.sub.2. The refrigerant compositions are useful in processes to produce cooling and heating, in methods for replacing refrigerant R-R-22, and in refrigeration, air conditioning or heat pump systems. These inventive compositions are non-flammable and match cooling performance for R-22. The compositions as described herein have unexpected flammability properties.

In accordance with the present invention refrigerant compositions are disclosed. The compositions comprise HFC-32, HFC-125, HFO-1234yf, HFC-134a, and CO.sub.2. The refrigerant compositions are useful in processes to produce cooling and heating, in methods for replacing refrigerant R-R-22, and in refrigeration, air conditioning or heat pump systems. These inventive compositions are non-flammable and match cooling performance for R-22. The compositions as described herein have unexpected flammability properties.

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises a tetrafluoropropene and at least one other component. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and fire suppression and fire extinguishing agents.

There are provided a refrigerating oil for refrigerant compositions in which good lubricity can be achieved when a refrigeration cycle is performed using a refrigerant having a sufficiently low GWP, a method for using the refrigerating oil, and use of the refrigerating oil. The refrigerating oil for a refrigerant composition contains a refrigerant containing trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and 2,3,3,3-tetrafluoro-1-propene (R1234yf).

A refrigeration cycle apparatus including a heat exchanger can decrease the material cost. An air conditioning apparatus (10) that is a refrigeration cycle apparatus includes a flammable refrigerant containing at least 1,2-difluoroethylene, an outdoor heat exchanger (23), and an indoor heat exchanger (27). One of the outdoor heat exchanger (23) and the indoor heat exchanger (27) is an evaporator that evaporates the refrigerant, and the other one is a condenser that condenses the refrigerant. The outdoor heat exchanger (23) and the indoor heat exchanger (27) each are a heat exchanger that includes metal plates (19) serving as a plurality of fins made of aluminum or an aluminum alloy, and flat tubes (16) serving as a plurality of heat transfer tubes made of aluminum or an aluminum alloy, and that causes the refrigerant flowing inside the flat tubes (16) and the air flowing along the metal plates (19) to exchange heat with each other. The refrigerant repeats a refrigeration cycle by circulating through the outdoor heat exchanger (23) and the indoor heat exchanger (27).

An apparatus and method wherein potential ozone layer-damaging chlorodifluoromethane (Refrigerant R-22) is substituted with a mix of less environmentally damaging refrigerants pentafluoroethane and tetrafluoroethane in chlorodifluoromethane-based air-cooling systems mainly in residential cooling. While less environmentally damaging than chlorodifluoromethane, the substitute refrigerant has a temperature-pressure relationship similar to that of chlorodifluoromethane, making the substitute refrigerant suitable for use with chlorodifluoromethane-based air-cooling systems. In this event, it is mixed with a relatively small percentage of a lubricating oil which is compatible with both the unit refrigerant and typical R-22 system design.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.