Abstract: A refrigeration cycle apparatus is caused to be in a normally operable state in accordance with the mixture ratio of difluoromethane occupying a refrigerant charged in the refrigeration cycle apparatus. A refrigeration cycle apparatus includes a refrigerant circuit including a compressor and performs a refrigeration cycle by circulating a refrigerant in the refrigerant circuit with the compressor. A heat-source-side controller judges the mixture ratio of difluoromethane occupying the refrigerant charged in the refrigerant circuit. The heat-source-side controller further performs control relating to the refrigeration cycle on the basis of the mixture ratio of difluoromethane judged by the judgement unit.

Abstract: Efficiency in refrigerant charging work is addressed when a recovered refrigerant recovered from a first heat source unit is to be charged to a second heat source unit. A refrigerant charging method is a charging method used when a first heat source unit of an already installed refrigeration cycle apparatus in which a refrigeration cycle is to be performed by a refrigerant that circulates is to be replaced with a second heat source unit. The refrigerant charging method includes recovering a first refrigerant from an already installed refrigeration cycle apparatus and obtaining a recovered refrigerant and charging the recovered refrigerant and charging a second refrigerant whose composition differs from the composition of the recovered refrigerant to the refrigeration cycle apparatus after renewal that includes the second heat source unit.

Abstract: A control unit (19) that controls the operation of a refrigerant circuit (10) executes pump down operation in which a non-azeotropic refrigerant mixture is collected into a portion of the refrigerant circuit (10) within an outdoor unit (2), executes compositional ratio determination in which the compositional ratio of the non-azeotropic refrigerant mixture is determined based on the pressure and temperature of the non-azeotropic refrigerant mixture collected into the outdoor unit (2) by the pump down operation, and generates an alert when the compositional ratio of the non-azeotropic refrigerant mixture determined by the compositional ratio determination is outside an acceptable proportion range of a hydrofluorocarbon having the property of undergoing a disproportionation reaction.

Abstract: Even if, in decompressing a refrigerant by an expansion mechanism, the temperature of the refrigerant cannot be sufficiently reduced, in order to increase the evaporation capacity of a use-side heat exchanger, a main expansion mechanism including an expansion element of a rotary or scroll type that causes power to be produced by decompressing a main refrigerant is provided at a main refrigerant circuit in which the main refrigerant circulates. Further, a sub-refrigerant circuit that differs from the main refrigerant circuit and in which a sub-refrigerant circulates is provided. A sub-use-side heat exchanger that is provided at the sub-refrigerant circuit and that functions as an evaporator of the sub-refrigerant is caused to function as a heat exchanger that cools the main refrigerant that flows between the main expansion mechanism and a main use-side heat exchanger.

Abstract: An air-conditioning unit that is able to suppress ignition at an electric heater even when leakage of refrigerant occurs while a low-GWP refrigerant is used is provided. In an outdoor unit (20) including a casing (60), a compressor (21) provided inside the casing (60) and configured to compress refrigerant containing 1,2-difluoroethylene, and a drain pan heater (54) provided inside the casing (60), an electric power consumption of the drain pan heater (54) is lower than or equal to 300 W.

Abstract: A refrigeration cycle apparatus (10) includes a refrigerant circuit (11) including a compressor (12), a heat source-side heat exchanger (13), an expansion mechanism (14), and a usage-side heat exchanger (15). In the refrigerant circuit (11), a refrigerant containing at least 1,2-difluoroethylene (HFO-1132 (E)) is sealed. At least during a predetermined operation, in at least one of the heat source-side heat exchanger (13) and the usage-side heat exchanger (15), a flow of the refrigerant and a flow of a heating medium that exchanges heating with the refrigerant are counter flows.

Abstract: A heat source unit and a refrigeration cycle apparatus that are able to reduce damage to a connection pipe when a refrigerant containing at least 1,2-difluoroethylene is used are provided. An outdoor unit (20) that is connected via a liquid-side connection pipe (6) and a gas-side connection pipe (5) to an indoor unit (30) including an indoor heat exchanger (31) and that is a component of an air conditioner (1) includes a compressor (21) and an outdoor heat exchanger (23). A refrigerant containing at least 1,2-difluoroethylene is used as a refrigerant. A design pressure of the outdoor unit (20) is lower than 1.5 times a design pressure of each of the liquid-side connection pipe (6) and the gas-side connection pipe (5).

Abstract: An air conditioning unit capable of performing a refrigeration cycle using a small-GWP refrigerant is provided. A refrigeration cycle apparatus (1, 1a to 1m) includes a refrigerant circuit (10) including a compressor (21), a condenser (23, 31, 36), a decompressing section (24, 44, 45, 33, 38), and an evaporator (31, 36, 23), and a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit (10).

Abstract: 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 D0/8 inches (where, “D0-? inches” is a pipe outer diameter of a connection pipe when refrigerant R32 is used), a range of the D0 of the liquid-side connection pipe (6) is “2?D0?4”, and a range of the D0 of the gas-side connection pipe (5) is “3?D0?8”.

Abstract: 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 D0/8 inches (where, “D0-? inches” is a pipe outer diameter of a connection pipe when refrigerant R32 is used), a range of the D0 of the liquid-side connection pipe (6) is “2?D0?4”, and a range of the D0 of the gas-side connection pipe (5) is “3?D0?8”.

Abstract: An air-conditioning unit that is able to suppress ignition at an electric heater even when leakage of refrigerant occurs while a low-GWP refrigerant is used is provided. In an outdoor unit (20) including a casing (60), a compressor (21) provided inside the casing (60) and configured to compress refrigerant containing 1,2-difluoroethylene, and a drain pan heater (54) provided inside the casing (60), an electric power consumption of the drain pan heater (54) is lower than or equal to 300 W.

Abstract: 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.

Abstract: A refrigeration cycle is a refrigeration cycle using a mixed refrigerant which is a flammable refrigerant and which contains at least 1,2-difluoroethylene (HFO-1132(E)), and includes a compressor (1), a heat-source-side heat exchanger (3), an expansion mechanism (4), a use-side heat exchanger (2), and a decompression mechanism (7). The decompression mechanism (7) decompresses, between an inlet and an outlet of the heat-source-side heat exchanger (3), the mixed refrigerant flowing through the heat-source-side heat exchanger (3) that functions as an evaporator.

Abstract: A two-stage refrigeration apparatus (500) includes a first cycle (510) and a second cycle (520). The first cycle (510) includes a first compressor (511), a first condenser (512), a first expansion mechanism (513), and a first evaporator (514) that are arranged in such a manner as to be connected to the first cycle. A first refrigerant circulates through the first cycle. The second cycle (520) includes a second downstream-side condenser (523) and a second evaporator (527) that are arranged in such a manner as to be connected to the second cycle. A second refrigerant circulates through the second cycle. The first evaporator (514) and the second downstream-side condenser (523) constitute a cascade condenser (531). In the cascade condenser (531), heat is exchanged between the first refrigerant and the second refrigerant. At least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (HFO-1132(E)).

Abstract: An air conditioning unit capable of performing a refrigeration cycle using a small-GWP refrigerant is provided. A refrigeration cycle apparatus (1, 1a to 1m) includes a refrigerant circuit (10) including a compressor (21), a condenser (23, 31, 36), a decompressing section (24, 44, 45, 33, 38), and an evaporator (31, 36, 23), and a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit (10).

Abstract: A refrigeration cycle apparatus that is able to reduce the amount of refrigerant used while reducing a pressure loss in the case where a refrigerant containing at least 1,2-difluoroethylene is used is provided. In an air conditioner (1) including a refrigerant circuit (10), including a compressor (21), an outdoor heat exchanger (23), an outdoor expansion valve (24), and an indoor heat exchanger (31), and a refrigerant containing at least 1,2-difluoroethylene and sealed in the refrigerant circuit (10), the outdoor heat exchanger (23) has a heat transfer tube (23b) of which a pipe diameter is greater than or equal to 6.35 mm and less than 10.0 mm.

Abstract: A refrigeration cycle apparatus (10) includes a refrigerant circuit (11) including a compressor (12), a heat source-side heat exchanger (13), an expansion mechanism (14), and a usage-side heat exchanger (15). In the refrigerant circuit (11), a refrigerant containing at least 1,2-difluoroethylene (HFO-1132 (E)) is sealed. At least during a predetermined operation, in at least one of the heat source-side heat exchanger (13) and the usage-side heat exchanger (15), a flow of the refrigerant and a flow of a heating medium that exchanges heating with the refrigerant are counter flows.

Abstract: A refrigeration cycle is a refrigeration cycle using a mixed refrigerant which is a flammable refrigerant and which contains at least 1,2-difluoroethylene (HFO-1132(E)), and includes a compressor (1), a heat-source-side heat exchanger (3), an expansion mechanism (4), a use-side heat exchanger (2), and a decompression mechanism (7). The decompression mechanism (7) decompresses, between an inlet and an outlet of the heat-source-side heat exchanger (3), the mixed refrigerant flowing through the heat-source-side heat exchanger (3) that functions as an evaporator.

Abstract: A two-stage refrigeration apparatus (500) includes a first cycle (510) and a second cycle (520). The first cycle (510) includes a first compressor (511), a first condenser (512), a first expansion mechanism (513), and a first evaporator (514) that are arranged in such a manner as to be connected to the first cycle. A first refrigerant circulates through the first cycle. The second cycle (520) includes a second downstream-side condenser (523) and a second evaporator (527) that are arranged in such a manner as to be connected to the second cycle. A second refrigerant circulates through the second cycle. The first evaporator (514) and the second downstream-side condenser (523) constitute a cascade condenser (531). In the cascade condenser (531), heat is exchanged between the first refrigerant and the second refrigerant. At least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (FO-1132(E)).

Abstract: A refrigeration cycle apparatus capable of keeping a LCCP low when a heat cycle is performed using a sufficiently small-GWP refrigerant, and a method of determining a refrigerant enclosure amount in the refrigeration cycle apparatus are provided. An outdoor unit (20) including a compressor (21) and an outdoor heat exchanger (23), an indoor unit (30) including an indoor heat exchanger (31), and a refrigerant pipe (5, 6) that connects the outdoor unit (20) and the indoor unit (30) to each other are provided. A refrigerant containing at least 1,2-difluoroethylene is enclosed in a refrigerant circuit (10) that is constituted by connecting the compressor (21), the outdoor heat exchanger (23), and the indoor heat exchanger (31) to one another. An enclosure amount of the refrigerant in the refrigerant circuit (10) per 1 kW of refrigeration capacity satisfies a condition of 160 g or more and 560 g or less.