Abstract: A gas detector detects difluoromethane present in a remote target space. The gas detector includes a detection portion that detects the difluoromethane by using absorption of light of a predetermined wavelength. The predetermined wavelength is in a wavelength range of any of a first wavelength range of 1659 to 1673 nm, a second wavelength range of 1724 to 1726 nm, a third wavelength range of 2218 to 2221 nm, a fourth wavelength range of 2463 to 2466 nm, a fifth wavelength range of 3316 to 3318 nm, and a sixth wavelength range of 9034 to 9130 nm.

Abstract: A refrigerant cycle system includes: a first refrigerant circuit that includes a first heat exchanger, a first compressor, and a first cascade heat exchanger and that is configured as a first vapor compression refrigeration cycle; a second refrigerant circuit that includes the first cascade heat exchanger, a second compressor, and a second heat exchanger and that is configured as a second vapor compression refrigeration cycle; a first unit that accommodates the first heat exchanger and the first compressor; a second unit that accommodates the first cascade heat exchanger and the second compressor; and a third unit that accommodates the second heat exchanger. The first unit, the second unit, and the third unit are disposed apart from each other. The first cascade heat exchanger performs heat exchange between a first refrigerant that flows through the first refrigerant circuit and a second refrigerant that flows through the second refrigerant circuit.

Abstract: A refrigerant cycle system includes a primary-side cycle that circulates a first refrigerant, a secondary-side cycle that circulates a second refrigerant, and a cascade heat exchanger that exchanges heat between the first refrigerant and the second refrigerant. The primary-side cycle includes a primary-side connection pipe. The secondary-side cycle includes a secondary-side connection pipe. The primary-side connection pipe includes a primary-side gas connection pipe and a primary-side liquid connection pipe. The secondary-side connection pipe includes a secondary-side gas connection pipe and a secondary-side liquid connection pipe. The pipe diameter of the secondary-side gas connection pipe is smaller than the pipe diameter of the primary-side gas connection pipe, or the pipe diameter of the secondary-side liquid connection pipe is smaller than the pipe diameter of the primary-side liquid connection pipe.

Abstract: A refrigerant cycle system includes: a primary-side cycle of a vapor compression type that circulates a first refrigerant; a secondary-side cycle of a vapor compression type that circulates a second refrigerant; and a cascade heat exchanger that exchanges heat between the first refrigerant and the second refrigerant. The secondary-side cycle includes a secondary-side heat exchanger that uses cold or heat obtained by the second refrigerant from the cascade heat exchanger. The secondary-side heat exchanger includes a flat multi-hole pipe.

Abstract: Refrigerant is caused to be in a superheating state without impairing the performance of a cascade heat exchanger. A refrigerant cycle system includes a first refrigerant circuit, a second refrigerant circuit, and a first cascade heat exchanger. The first cascade heat exchanger exchanges heat between a first refrigerant that flows in the first refrigerant circuit and a second refrigerant that flows in the second refrigerant circuit. The refrigerant cycle system includes a switching mechanism. The switching mechanism switches a flow path of a refrigerant of at least either one of the first refrigerant circuit and the second refrigerant circuit. The first cascade heat exchanger includes a first main heat exchanging unit acid a first sub heat exchanging unit. The first sub heat exchanging unit is configured to cause the first refrigerant that has passed through the first main heat exchanging unit to be in a superheating state.

Abstract: In a refrigeration cycle apparatus, a switching mechanism includes a first channel and performs switching among a first, second and third connection states. In the first connection state, the refrigeration cycle apparatus repeatedly performs a first cycle in which refrigerant flows through a compressor, a first heat exchanger, a second heat exchanger, and the compressor in that order. In the second connection state, the refrigeration cycle apparatus repeatedly performs a second cycle in which refrigerant flows through the compressor, the second heat exchanger, the first heat exchanger, and the compressor in that order. In the third connection state, a passage between the compressor and the first heat exchanger and a passage between the compressor and the second heat exchanger are closed, and the first channel in the refrigeration cycle apparatus provides interconnection between the first heat exchanger and the second heat exchanger.

Abstract: To reduce the possibility that temperature of refrigerant discharged from a compressor of a refrigeration apparatus becomes excessively high by controlling torque of a motor built into the compressor, the compressor includes the motor having rotation thereof controlled by inverter control. An inverter controller controls torque of the motor using inverter control when operation frequency of the compressor is at least one value within a range of from 10 Hz to 40 Hz. When at least the operation frequency is within the range of from 10 Hz to 40 Hz, torque of the motor is controlled, and under a predetermined condition in which temperature of refrigerant discharged from the compressor easily becomes excessively high, a device controller controls devices provided in a refrigerant circuit such that refrigerant sucked into the compressor is placed in a wet vapor state.

Abstract: A method of searching for a refrigerant leak location is provided which can easily specify the refrigerant leak location. In the method of searching for the refrigerant leak location in a refrigeration apparatus (100) in which a refrigerant is charged and which includes a refrigeration circuit (10) performing a refrigeration cycle, the refrigeration circuit (10) is prepared in a state that the refrigerant containing an odor component is charged therein, and the refrigerant leak location is specified by letting a dog capable of detecting the odor component to run along the refrigeration circuit (10).

Abstract: Provided is a refrigeration apparatus that is capable of determining an increased possibility of ignition due to a refrigerant leak. An air conditioner (100) including a refrigerant circuit (10) includes a refrigerant gas sensor (81) and an oxygen gas sensor (82). The refrigerant circuit (10) has an R32 refrigerant charged therein, and performs a refrigeration cycle. The refrigerant gas sensor (81) detects a refrigerant gas in a room where at least a portion of the air conditioner (100) is located. The oxygen gas sensor (82) detects an oxygen gas in the room.

Abstract: Provided is an indoor unit for a refrigeration apparatus that is capable of detecting a refrigerant leak while suppressing condensation on a refrigerant gas sensor. An indoor unit (50) for an air conditioner (100) including a refrigerant circuit (10) includes a casing (60), an indoor fan (53), and a refrigerant gas sensor (81). The refrigerant circuit (10) has refrigerant charged therein, and performs a refrigeration cycle. The casing (60) houses at least a portion of the refrigerant circuit (10), and has a blow-out port (64) that opens in a direction other than an up-down direction. The indoor fan (53) is housed in the casing (60), and generates an air flow (F) directed from the blow-out port (64) to outside the casing (60). The refrigerant gas sensor (81) is capable of detecting a refrigerant gas below a bottom surface (63) of the casing (60).

Abstract: To reduce the possibility that temperature of refrigerant discharged from a compressor of a refrigeration apparatus becomes excessively high by controlling torque of a motor built into the compressor, the compressor includes the motor having rotation thereof controlled by inverter control. An inverter controller controls torque of the motor using inverter control when operation frequency of the compressor is at least one value within a range of from 10 Hz to 40 Hz. When at least the operation frequency is within the range of from 10 Hz to 40 Hz, torque of the motor is controlled, and under a predetermined condition in which temperature of refrigerant discharged from the compressor easily becomes excessively high, a device controller controls devices provided in a refrigerant circuit such that refrigerant sucked into the compressor is placed in a wet vapor state.

Abstract: To reduce the possibility that temperature of refrigerant discharged from a compressor of a refrigeration apparatus becomes excessively high by controlling torque of a motor built into the compressor, the compressor includes the motor having rotation thereof controlled by inverter control. An inverter controller controls torque of the motor using inverter control when operation frequency of the compressor is at least one value within a range of from 10 Hz to 40 Hz. When at least the operation frequency is within the range of from 10 Hz to 40 Hz, torque of the motor is controlled, and under a predetermined condition in which temperature of refrigerant discharged from the compressor easily becomes excessively high, a device controller controls devices provided in a refrigerant circuit such that refrigerant sucked into the compressor is placed in a wet vapor state.

Abstract: Provided is a refrigeration apparatus that is capable of determining an increased possibility of ignition due to a refrigerant leak. An air conditioner (100) including a refrigerant circuit (10) includes a refrigerant gas sensor (81) and an oxygen gas sensor (82). The refrigerant circuit (10) has an R32 refrigerant charged therein, and performs a refrigeration cycle. The refrigerant gas sensor (81) detects a refrigerant gas in a room where at least a portion of the air conditioner (100) is located. The oxygen gas sensor (82) detects an oxygen gas in the room.

Abstract: Provided is an indoor unit for a refrigeration apparatus that is capable of detecting a refrigerant leak while suppressing condensation on a refrigerant gas sensor. An indoor unit (50) for an air conditioner (100) including a refrigerant circuit (10) includes a casing (60), an indoor fan (53), and a refrigerant gas sensor (81). The refrigerant circuit (10) has refrigerant charged therein, and performs a refrigeration cycle. The casing (60) houses at least a portion of the refrigerant circuit (10), and has a blow-out port (64) that opens in a direction other than an up-down direction. The indoor fan (53) is housed in the casing (60), and generates an air flow (F) directed from the blow-out port (64) to outside the casing (60). The refrigerant gas sensor (81) is capable of detecting a refrigerant gas below a bottom surface (63) of the casing (60).

Abstract: A method of searching for a refrigerant leak location is provided which can easily specify the refrigerant leak location. In the method of searching for the refrigerant leak location in a refrigeration apparatus (100) in which a refrigerant is charged and which includes a refrigeration circuit (10) performing a refrigeration cycle, the refrigeration circuit (10) is prepared in a state that the refrigerant containing an odor component is charged therein, and the refrigerant leak location is specified by letting a dog capable of detecting the odor component to run along the refrigeration circuit (10).

Abstract: Dehumidification cannot be performed when a load decreases. In an air conditioner of the present invention, an indoor heat exchanger includes an auxiliary heat exchanger 20 and a main heat exchanger 21 disposed leeward from the auxiliary heat exchanger 20. In an operation in a predetermined dehumidification operation mode, a liquid refrigerant supplied to the auxiliary heat exchanger 20 all evaporates midway in the auxiliary heat exchanger 20. Therefore, only an upstream partial area in the auxiliary heat exchanger 20 is an evaporation region, while an area downstream of the evaporation region in the auxiliary heat exchanger 20 is a superheat region. In the predetermined dehumidification operation mode, a compressor and an expansion valve are controlled so that the extent of the evaporation region of the auxiliary heat exchanger 20 varies depending on the load.

Abstract: To reduce the possibility that temperature of refrigerant discharged from a compressor of a refrigeration apparatus becomes excessively high by controlling torque of a motor built into the compressor, the compressor includes the motor having rotation thereof controlled by inverter control. An inverter controller controls torque of the motor using inverter control when operation frequency of the compressor is at least one value within a range of from 10 Hz to 40 Hz. When at least the operation frequency is within the range of from 10 Hz to 40 Hz, torque of the motor is controlled, and under a predetermined condition in which temperature of refrigerant discharged from the compressor easily becomes excessively high, a device controller controls devices provided in a refrigerant circuit such that refrigerant sucked into the compressor is placed in a wet vapor state.

Abstract: When a fully-closable expansion valve is used, there is a possibility that the expansion valve is fully closed thereby to block a refrigerant circuit. In an air conditioner 1 of the present invention, an indoor heat exchanger 14 includes an auxiliary heat exchanger 20 and a main heat exchanger 21 disposed leeward from the auxiliary heat exchanger 20. In an operation in a predetermined dehumidification operation mode, a liquid refrigerant supplied to the auxiliary heat exchanger 20 all evaporates midway in the auxiliary heat exchanger 20, i.e., before reaching the outlet. Therefore, only an upstream partial area in the auxiliary heat exchanger 20 is an evaporation region, while an area downstream of the evaporation region in the auxiliary heat exchanger 20 is a superheat region. Further, an evaporation temperature sensor 30 which detects an evaporation temperature is disposed downstream of an expansion valve 13 in an outdoor unit 3.

Abstract: A rotary type channel switching valve for use in a heat pump system is provided. The channel switching valve provides a plurality of channel switching means required when switching connection of a plurality of devices to parallel/series connection, e.g., in a system including the plurality of devices including inlet/outlet ports for a fluid. The channel-switching valve can play a role of a plurality of channel switching means which are required when connecting a plurality of heat exchangers in parallel when a refrigerant is passed in a normal direction, and when connecting a plurality of heat exchangers in series when the refrigerant is passed in a reverse direction, for example, in a heat pump including the plurality of heat exchangers, and thereby, can realize simplification of a configuration of the heat pump, reduction in an occupied space, cost and energy consumption, or the like.

Abstract: Dehumidification cannot be performed when a load decreases. In an air conditioner of the present invention, an indoor heat exchanger includes an auxiliary heat exchanger 20 and a main heat exchanger 21 disposed leeward from the auxiliary heat exchanger 20. In an operation in a predetermined dehumidification operation mode, a liquid refrigerant supplied to the auxiliary heat exchanger 20 all evaporates midway in the auxiliary heat exchanger 20. Therefore, only an upstream partial area in the auxiliary heat exchanger 20 is an evaporation region, while an area downstream of the evaporation region in the auxiliary heat exchanger 20 is a superheat region. In the predetermined dehumidification operation mode, a compressor and an expansion valve are controlled so that the extent of the evaporation region of the auxiliary heat exchanger 20 varies depending on the load.