An air conditioner may include a continuous refrigeration apparatus including a first gas control unit connected to a first indoor heat exchanger, a second gas control unit connected to a second indoor heat exchanger, a first pipe connecting a liquid pipe of an outdoor unit and a liquid of an indoor unit, and a second pipe branched from the first pipe and connected to the first and second gas control units. The first gas control unit may include a first-first flow path connecting the first gas control unit to the second pipe; a first-second flow path connected to the first-first flow path, and through which refrigerant discharged from the first indoor heat exchanger flows during a refrigeration operation; and a first-third flow path connected in parallel with the first-second flow path, and guiding refrigerant from the compressor to the first indoor heat exchanger during a defrosting operation.

An air conditioner comprises a compressor configured to have an inlet, through which a refrigerant is sucked in, the sucked refrigerant being compressed by the compressor, and an outlet, through which the compressed refrigerant is discharged, a four-way valve configured to switch flow paths in cooling and heating operations, the four-way valve having a valve body, a D port protruding from the valve body in a first direction to be connected to the outlet, and an S port 26 protruding from the valve body in a second direction, which is opposite to the first direction, to be connected to the inlet, and a compressor pipe having a discharging pipe to connect the outlet and the D port and a sucking pipe to connect the inlet and the S port, one of the discharging pipe and the sucking pipe has two curved portions and the other has one curved portion.

In a refrigeration cycle apparatus according to the present disclosure, the circulation direction of refrigerant is switched between a first circulation direction and a second circulation direction opposite to the first circulation direction. The first circulation direction is a circulation direction in order of a compressor, a first heat exchanger, a first expansion valve, a third heat exchanger, a fourth heat exchanger, a second expansion valve, and a second heat exchanger. When a circulation direction of the refrigerant is the first circulation direction, the refrigerant from the third heat exchanger exchanges heat with the refrigerant from the second heat exchanger in the fourth heat exchanger. When a circulation direction of the refrigerant is the second circulation direction, the refrigerant from the fourth heat exchanger exchanges heat with the refrigerant from the first heat exchanger in the third heat exchanger.

A defrosting control method for a multi-split system is provided. A multi-split system comprises an outdoor unit and multiple indoor units. An expansion valve is provided on a connecting pipeline between each of the indoor units and the outdoor unit. When the expansion valve of each activated indoor unit is closed and the degree of opening of the expansion valve of each off-state indoor unit is less than or equal to a maximum set degree of opening, the system satisfies a defrosting requirement, and as a result the method controls the expansion valve of each activated indoor unit to remain closed, thereby resolving the issue of a dramatic temperature drop in a room having an activated indoor unit during defrosting and improving user satisfaction. The degree of opening of the expansion valve of a off-state indoor unit is Off_PLS, and is controlled such that Off_PLS=ALL_HP*Avg_PLS/Off_HP. The invention satisfies a defrosting requirement and reduces the degree of opening of the expansion valves as much as possible, thereby preventing damage to a compressor without affecting defrosting.

An air-conditioning system includes: an air conditioner including an outdoor unit and a plurality of indoor units each provided in a corresponding one of a plurality of indoor spaces and each including a first control unit; and a second control unit capable of communicating with the first control units. Each first control unit is capable of communicating with a countermeasure device if the countermeasure device is installed in correspondence with one of the indoor spaces where the first control unit is located. The second control unit has a first function of prohibiting operation of the air conditioner if a first condition where communication between the first control unit and the countermeasure device is not established in any of the indoor units is satisfied.

An air-conditioning apparatus includes a refrigeration circuit, a first shut-off device provided at a pipe connecting a heat-source-side heat exchanger and an expansion device, a refrigerant leak detection device, and a controller. The controller controls a flow switching device to switch a connection state between a first connection state in which a discharge side of a compressor is connected to the heat-source-side heat exchanger, and a second connection state in which a suction side of the compressor is connected to the heat-source-side heat exchanger via an accumulator. When a refrigerant leak is detected, the controller performs a refrigerant retrieval operation and a refrigerant transfer operation.

The application relates to an air conditioner/heat pump expansion function box and an air conditioner/heat pump heat storage refrigeration system, and belongs to the technical field of air conditioner/heat pump systems. Two distribution pipelines are arranged in the air conditioner/heat pump expansion function box body; each distribution pipeline comprises a main pipeline and at least one branch pipeline; the two ends of each main path are provided with an outdoor unit nut head and an indoor unit nut head respectively. The end portion, far away from the main path, of each branch path is provided with a radiation assembly nut head; an outdoor unit nut head is connected with an outdoor unit, an indoor unit nut head is connected with an indoor unit, and a radiation assembly nut head is connected with a radiation assembly. Therefore, an air conditioner/heat pump heat storage refrigeration system is formed, reasonable distribution of water-free floor heating pipelines is achieved, the energy efficiency ratio of the air conditioner/heat pump system is increased, pipeline connection of a unit is achieved under the non-oxidation condition, it is guaranteed that no impurities exist in the system pipelines, the service life of the unit is long, the assembling efficiency is improved, no welding process exists on site, operation is easy, and the appearance is attractive.

At a refrigeration cycle device, an injection pipe and an economizer heat exchanger are provided at a main refrigerant circuit. In addition, the refrigeration cycle device includes a sub-refrigerant circuit having a sub-usage-side heat exchanger. At the refrigeration cycle device, the sub-usage-side heat exchanger functions as an evaporator of a sub-refrigerant and cools a main refrigerant that has been cooled at the economizer heat exchanger, or functions as a radiator of the sub-refrigerant and heats the main refrigerant that has been cooled at the economizer heat exchanger.

A heat pump system includes a first heat pump and a second heat pump. The first heat pump includes a first outdoor unit. The first outdoor unit includes a compressor, an outdoor-unit connecting pipe, and a refrigerant filling port. The outdoor-unit connecting pipe connects an intake path of the compressor and a second outdoor unit of the second heat pump for supplying a refrigerant to the second outdoor unit of the second heat pump. The refrigerant filling port is provided in a portion of the outdoor-unit connecting pipe.

A heat pump apparatus includes a refrigerant circuit and a heat medium circuit. The refrigerant circuit performs a first operation using a load-side heat exchanger as a condenser, and a second operation using the load-side heat exchanger as an evaporator. A suction pipe provided between a refrigerant flow switching valve and a compressor has a container. To the heat medium circuit, an overpressure protection relief valve and a refrigerant leakage detector are connected. When leakage of refrigerant into the heat medium circuit is detected, the refrigerant flow switching valve is switched to a second state, an expansion device is set to a closed state, and the compressor is operated. When a requirement for ending the operation of the compressor is satisfied after the leakage is detected, the compressor is stopped, and the refrigerant flow switching valve is switched to a first state.