A valve body in each of heat medium flow switching devices has an open portion. When the length from a connection between a first passage pipe and a third passage pipe to a connection between a second passage pipe and the third passage pipe is defined as a casing passage width, a valve body passage width of the open portion in a direction substantially perpendicular to the axis of the valve body is smaller than the casing passage width.

A channel on an upstream side of a third expansion device and a channel on an upstream side of a second expansion device are connected during a heating operation, and medium pressure refrigerant generated by the third expansion device during the heating operation is introduced on a suction side of a compressor via the second expansion device and a suction injection pipe.

An icemaking system includes a circulation circuit configured to circulate icemaking solution, at least one icemaker provided in the circulation circuit, a cooling mechanism, a first detector and an adjuster. The icemaker includes a cooling chamber and a scraping mechanism. The cooling chamber has an inflow port and an exhaust port of solution, and the cooling chamber allows the solution to flow in the cooling chamber. The scraping mechanism scrapes ice generated on an inner surface of the cooling chamber. The cooling mechanism cools the solution in the cooling chamber. The first detector detects whether the inflow port of the cooling chamber has an ice nucleus. The adjuster adjusts a cooling temperature of the solution in accordance with a detection result of the first detector.

A refrigeration cycle apparatus includes a refrigerant circuit in which a compressor, a refrigerant flow switching device, an air-side heat exchanger, an expansion valve, a water-side heat exchanger, and an accumulator are connected by refrigerant pipes and refrigerant is circulated. G/A is less than or equal to a predetermined threshold χ, where G [L] is a difference in volume between the air-side heat exchanger and the water-side heat exchanger, and A [L] is a volume of the refrigerant circuit.

A non-stop defrosting multi-connected hot water system and a control method. Heat is recovered by utilizing the characteristic of a phase-change heat storage module that can store heat, and then the heat is released during defrosting. In a defrosting process, modes of a hydraulic module and an indoor unit are not changed, and a four-way valve is not reversed, so as to avoid the influence of the defrosting process on an indoor ambient temperature and a water temperature of the hydraulic module, and avoid the condition where a liquid refrigerant generated in the defrosting process does not evaporate and directly flows back into a compressor which causes liquid return of the compressor, thus improving the reliability of the overall operation of the system.

A controller performs a first operation in which a heat source device directly or indirectly heats water in a first channel of a heat exchanger and a second operation in which the heat source device directly or indirectly cools the water in the first channel of the heat exchanger after the first operation ends.

An air conditioning apparatus includes, a first heat exchanger, a second heat exchanger configured to exchange heat between a first heat medium and a second heat medium, flow rate control valves, and a pump. In a heating mode, a controller is configured to open the flow rate control valve corresponding to a heat exchanger, of the third heat exchangers, to which a request for air conditioning has been made, and to close the flow rate control valve(s) corresponding to a heat exchanger(s), of the third heat exchangers, to which the request for air conditioning has not been made. In a defrosting mode, when a temperature of the second heat medium is lower than a first determination temperature, the controller is configured to open at least one of the flow rate control valve(s) corresponding to the heat exchanger(s) to which the request for air conditioning has not been made.

An air conditioning apparatus includes a heat exchange device that connects an outdoor unit to an indoor unit and that includes a heat exchanger configured to perform heat exchange between refrigerant and water, thereby reducing an amount of refrigerant used to perform a cooling operation or a heating operation. The apparatus further includes a switching mechanism that connects the outdoor unit to the heat exchange device and that is configured to be connected to both a simultaneous outdoor unit and a switchable outdoor unit to thereby allow the heat exchange device to be installed regardless of the type of the outdoor unit.

A multi-connected heat recovery air conditioning system and a control method thereof. The multi-connected heat recovery air conditioning system includes an indoor unit, an outdoor unit and a hydraulic module, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger, a first four-way valve and a second four-way valve. The multi-connected heat recovery air conditioning system further comprises an indoor unit temperature unit, a water temperature unit, a high-pressure sensor and a low-pressure sensor. The indoor unit temperature unit is arranged in the indoor unit for detecting and obtaining the outlet temperature value of the indoor unit, the water temperature unit is arranged at a heat exchange water tank for detecting and obtaining water temperature, and the high-pressure sensor and the low-pressure sensor are arranged at the output end and the air return end of the compressor respectively.

A system for air-conditioning and hot-water supply is configured to selectively perform a cooling operation and a heating operation. The system includes: an outdoor unit having a compressor and an outdoor heat exchanger; at least one or more indoor units each of which is connected to the outdoor unit and includes an indoor heat exchanger; a hot-water supply unit connected to the outdoor unit so as to be arranged in parallel to the at least one or more indoor units and including a refrigerant-water heat exchanger; and a controller configured to monitor an occurrence of a request for hot-water supply from the hot-water supply unit during the cooling operation performed at at least one of the indoor units, and then to start the heating operation. The controller is further configured to determine a time point to resume the cooling operation based on at least one of an outdoor temperature and a target temperature of at least one indoor unit in the heating operation.