Abstract: A controller has a timer operation mode in which the operation of a refrigeration cycle that operates as a heat source or a cold source is started before a set operation start time of an indoor fan by a preliminary operation time period. In the timer operation mode, the controller calculates a heat capacity of water or brine, calculates a heat storage amount of a second heat medium from a temperature detected by a temperature sensor and the heat capacity, and determines the preliminary operation time period from the heat storage amount. By determining the preliminary operation time period in this manner, timer operation can be performed such that air at an appropriate temperature is blown from an indoor unit at the operation start time of the indoor fan, from the initial time at which an air conditioning apparatus is installed.

Abstract: An air conditioning apparatus uses a heat medium containing at least one of cold water and hot water. The air conditioning apparatus includes: a heat source device; a heat exchanger configured to exchange heat between the heat medium and air; a flow rate control valve configured to control a flow rate at which the heat medium is supplied to the heat exchanger; a temperature sensor configured to detect a temperature of the heat medium discharged from the heat exchanger; and a failure determination unit configured to detect presence or absence of an abnormality in a flow path of the heat medium based on the temperature detected by the temperature sensor and a commanded degree of opening for the flow rate control valve.

Abstract: Provided is an ambient temperature estimating device, ambient temperature estimating method, program, and system that are able to realize both high robustness and high ambient temperature estimation accuracy. An ambient temperature estimating device includes a neural network, a temperature acquisition unit configured to acquire one or more temperature values inside the ambient temperature estimating device, and a neural network calculator configured to estimate an ambient temperature around the ambient temperature estimating device using the neural network. Input values inputted to the neural network by the neural network calculator include the temperature values acquired by the temperature acquisition unit and a heat source control value for controlling a heat source inside the ambient temperature estimating device.

Abstract: A refrigeration cycle apparatus includes a hot water tank, a heat source for heating water in the hot water tank, and a refrigeration cycle circuit that includes an indoor heat exchanger, a heat-source heat exchanger, and a water heat exchanger. The indoor heat exchanger may operate as a condenser. When an outside temperature is greater than a specified temperature, the refrigeration cycle apparatus operates in a first state in which the heat-source heat exchanger operates as an evaporator and the water heat exchanger does not operate. When the outside temperature is less than the specified temperature, the refrigeration cycle apparatus operates in a second state in which the water heat exchanger operates as an evaporator and refrigerant therein absorbs heat from water in the hot water tank heated by the heat source and the heat-source heat exchanger does not operate.

Abstract: A thermoelectric power generator includes: a pipe in which a first fluid flows; a power generation module including a thermoelectric conversion element; and a holding member that is in contact with a one side part of the power generation module, such that heat of a second fluid that is higher in temperature than the first fluid transfers to the one side part of the power generation module. The holding member holds the power generation module and the pipe in a heat transferable state, such that the pipe is in contact with the other side part of the power generation module. The thermoelectric power generator includes a heat conductive component interposed between the holding member and the pipe to define a heat transfer course through which heat transfers from the second fluid to the first fluid, at downstream of the power generation module in a flowing direction of the second fluid.

Abstract: An air conditioning device has: a refrigerant circuit that is formed of a compressor, a switching valve, a cascade heat exchanger, an expansion valve and an outdoor heat exchanger connected to one another by a first pipe through which a refrigerant flows, and capable of performing a defrosting operation in which the refrigerant discharged from the compressor is introduced into the outdoor heat exchanger; a heat-transfer medium circuit that is formed of a pump, the cascade heat exchanger, and the indoor heat exchanger connected to one another by a second pipe through which a heat-transfer medium flows; and a control device that controls the compressor and the pump. When an amount of heat storage of the heat-transfer medium is less than a threshold, the control device reduces the heating capability of the indoor heat exchanger when the air conditioning device transitions from a heating operation to the defrosting operation.

Abstract: A refrigeration cycle apparatus includes a gas leakage sensor and a control device. When refrigerant leakage is detected by the gas leakage sensor, the control device performs a first mode operation to operate a compressor in such a state that a four-way valve is set to a cooling operation state, an expansion valve is opened, and a first shutoff valve is closed. After performing the first mode operation, the control device performs a second mode operation to operate the compressor in such a state that the four-way valve is set to a heating operation state and the first shutoff valve is closed.

Abstract: An air conditioning system includes: a plurality of indoor units each configured to condition air in a target space; and an outdoor unit connected to the plurality of indoor units. Each of the plurality of indoor units has a surface temperature measuring device configured to measure a surface temperature of an object in the target space. When a total of capacities requested by the plurality of indoor units is larger than a capacity of the outdoor unit, each of the plurality of indoor units performs a process corresponding to a change amount of the surface temperature per unit time.

Abstract: A space in which an indoor unit is disposed has its corresponding refrigerant leakage sensor. A remote control for the indoor unit has its corresponding information output device for notifying the user of information visually and/or aurally. When the refrigerant leakage sensor detects a leakage of refrigerant, an alarm outputs a warning sound and a safety measure device is activated. Further, the information output device outputs guidance information for notifying the user action to be taken after the safety measure device takes the safety measure. After outputting the guidance information, the information output device stops outputting the guidance information in response to completion of the user action.

Abstract: The refrigerant circuit includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, and a second flow path switching unit. The outdoor heat exchanger has a plurality of first flat heat transfer tubes, a plurality of second flat heat transfer tubes, and a plurality of third flat heat transfer tubes. The second flow path switching unit switches the refrigeration cycle apparatus between a third state and a fourth state. In the third state, the plurality of first flat heat transfer tubes and the plurality of third flat heat transfer tubes are sequentially connected in series. In the fourth state, the plurality of first flat heat transfer tubes, the plurality of second flat heat transfer tubes, and the plurality of third flat heat transfer tubes are connected in parallel to each other.

Abstract: A storage device of a system control device stores grouping information that defines an association among a refrigerant sensor, a plurality of indoor units, at least one outdoor unit, and a plurality of refrigerant leakage suppression devices. When refrigerant leakage is detected by the refrigerant sensor, the system control device performs a process for specifying, from the plurality of indoor units, an indoor unit in which the refrigerant leakage has occurred. Further, the system control device makes reference to the grouping information to operate a refrigerant leakage suppression device corresponding to the indoor unit specified by performing the above-described process.

Abstract: A second fluid having a higher temperature than a first fluid, which flows in a duct, flows in contact with outside fins. Opposed regions of each power generation module and the duct apply pressure to and in contact with each other. Opposed regions of each power generation module and a corresponding one of a first outside plate and a second outside plate apply pressure to and in contact with each other. The duct is formed from a material having a thermal expansion coefficient larger than the first outside plate and the second outside plate. Additionally, two power generation modules are not necessarily required, and at least one power generation module is provided.

Abstract: A refrigeration cycle apparatus capable of performing pump down operation while suppressing degradation in performance is provided. The refrigeration cycle apparatus includes an outdoor heat exchanger, a compressor including an inlet side and an outlet side, at least one indoor heat exchanger, a four-way valve, a check valve including an inlet side and an outlet side, a pipe serving as a first flow path connecting the outlet side of the check valve to the inlet side of the compressor, a first on-off valve, and a refrigerant leak detection device. The refrigeration cycle apparatus is configured such that, when a refrigerant leak is detected by the refrigerant leak detection device, pump down operation is performed as refrigerant transfer operation of transferring the refrigerant from the indoor heat exchanger to the outdoor heat exchanger.

Abstract: A thermoelectric power generator includes: a pipe in which a first fluid flows; a power generation module including a thermoelectric conversion element; and a holding member that is in contact with a one side part of the power generation module, such that heat of a second fluid that is higher in temperature than the first fluid transfers to the one side part of the power generation module. The holding member holds the power generation module and the pipe in a heat transferable state, such that the pipe is in contact with the other side part of the power generation module. The thermoelectric power generator includes a heat conductive component interposed between the holding member and the pipe to define a heat transfer course through which heat transfers from the second fluid to the first fluid, at downstream of the power generation module in a flowing direction of the second fluid.

Abstract: An air-conditioning system according to an embodiment of the present disclosure is an air-conditioning system that conditions air of a room partitioned into a plurality of rectangular air-conditioning target areas in a plan view, and includes a use-side unit that is installed above a ceiling of one of the air-conditioning target areas and is configured to perform air-conditioning operation to condition air of the one air-conditioning target area.

Abstract: A heat exchanger group includes a first heat exchanger, a second heat exchanger, and a third heat exchanger. In a cooling operation, refrigerant discharged from the compressor is divided into two. One refrigerant is delivered to the second heat exchanger, and the other refrigerant is delivered to the third heat exchanger. The second heat exchanger performs heat exchange to turn the refrigerant into two-phase refrigerant. The third heat exchanger performs heat exchange to turn the refrigerant into two-phase refrigerant. The refrigerant that has flowed through the second heat exchanger and the refrigerant that has flowed through the third heat exchanger meet, and the resultant refrigerant is delivered to the first heat exchanger. The first heat exchanger performs heat exchange, so that the two-phase refrigerant turns into liquid refrigerant and flows through the first heat exchanger.

Abstract: An air conditioning apparatus uses a heat medium containing at least one of cold water and hot water. The air conditioning apparatus includes: a heat source device; a heat exchanger configured to exchange heat between the heat medium and air; a flow rate control valve configured to control a flow rate at which the heat medium is supplied to the heat exchanger; a temperature sensor configured to detect a temperature of the heat medium discharged from the heat exchanger; and a failure determination unit configured to detect presence or absence of an abnormality in a flow path of the heat medium based on the temperature detected by the temperature sensor and a commanded degree of opening for the flow rate control valve.

Abstract: A refrigeration cycle apparatus includes a compressor, a four-way valve, a second flow path switching unit, a first outdoor heat exchanger, a second outdoor heat exchanger, a first indoor heat exchanger and a second flow path switching unit. The second flow path switching unit switches between a third state in which the first port, the second port, the first outdoor heat exchanger, the fourth port, the third port, the second heat exchanger, the fifth port and the sixth port are successively connected in series, and a fourth state in which the sixth port, the fourth port, the first heat exchanger, the second port and the first port are successively connected in series, and the sixth port, the fifth port, the second heat exchanger, the third port and the first port are successively connected in series.

Abstract: A fluid passage structure includes a housing and first wall portions. The housing includes an outer surface located at an end of a first direction and two passages separated from each other provided inside. Each of two passages includes at least one fluid chamber, openings that open to the outer surface, and branch paths that is coupled to the fluid chamber. The fluid chambers of the two passages are arranged alternately in the first direction. The branch paths include at least one of: branch paths that couple at least one of the openings with one fluid chamber; and branch paths that couple one fluid chamber with another fluid chamber. The first wall portions are provided in the housing, face the fluid chamber, and are arranged in the first direction via the fluid chamber.