An air conditioner includes a heat source unit having a compressor, a first heat exchanger configured to cause heat exchange between a refrigerant and liquid fluid, a second heat exchanger configured to cause heat exchange between the refrigerant and air, and a valve configured to switch to supply or not to supply the second heat exchanger with the refrigerant, and a controller configured to control to operate the compressor and to open or close the valve. The controller opens the valve to supply the second heat exchanger with the refrigerant to cause the second heat exchanger to function as a heat absorber when assessing that the refrigerant sent to the utilization unit needs to be decreased in quantity during cooling operation in which the first heat exchanger functions as a radiator.

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.

A multi-air conditioner for heating and cooling may include at least one indoor unit for both cooling and heating including an indoor heat exchanger; an outdoor unit for both cooling and heating including a compressor, a plurality of outdoor heat exchangers, and a switching unit disposed on a discharge side of the compressor to switch a flow of refrigerant; and a distributor disposed between the outdoor unit and the at least one indoor unit, that distributes the refrigerant. The plurality of outdoor heat exchangers in the outdoor unit may include a first heat exchanger, a first end of which is connected to the switching unit, and a second end of which is connected to the distributor; a second heat exchanger disposed under the first heat exchanger, a first end of which is configured to be coupled to or decoupled from the second end of the first heat exchanger, and a second end of which is connected to the distributor; and a third heat exchanger disposed under the second heat exchanger, a first end of which is connected to the discharge side of the compressor, and a second end of which is connected to the indoor unit.

An air conditioner allows refrigerant to circulate therethrough. The air conditioner includes a compressor, a first heat exchanger, a first expansion valve, a second heat exchanger, and a controller. The controller changes an opening degree of the first expansion valve by a first operation amount according to a temperature difference between a target temperature and the temperature of the refrigerant discharged by the compressor. The refrigerant circulates through the compressor, the first heat exchanger, the first expansion valve, and the second heat exchanger. A first ratio when a specific condition is satisfied is larger than a second ratio when the specific condition is not satisfied. The specific condition indicates that the degree of subcooling of the refrigerant flowing between the first heat exchanger and the first expansion valve is smaller than zero. The first and second ratios are each a ratio of the first operation amount to the temperature difference.

Provided are a three-tube heat recovery multi-split air conditioning system and control method for the same, the system including: an outdoor unit; an indoor unit; a refrigerant distribution device, including a heat exchange assemble, a cooling-heating switching valve, and a low temperature cooling and anti-freezing module; and a controller, configured to acquire an evaporation temperature of the cooling indoor unit and an outdoor ambient temperature when the three-tube heat recovery multi-split air conditioning system operates in a cooling mode or a mixed operation mode, determine whether the evaporation temperature of the cooling indoor unit requires to be adjusted according to the evaporation temperature of the cooling indoor unit and the ambient temperature, and control the low temperature cooling and anti-freezing module to adjust the evaporation temperature of the cooling indoor unit if the evaporation temperature of the indoor unit requires to be adjusted.

Systems and methods for controlled subcooling of working fluid in a heating, ventilation, air conditioning and refrigeration (HVACR) system through a suction line heat exchanger are disclosed. The suction line heat exchanger may receive a first fluid flow travelling to a suction of the compressor in the HVACR system and second flow of working fluid that is travelling from a heat exchanger receiving the discharge of the compressor to an expansion device. Superheating of the first working fluid may be determined based on temperature measurements prior to and following the suction line heat exchanger. The superheating may be used to control the quantity of the second flow of working fluid introduced into the suction line heat exchanger, for example to maintain superheat that is below a threshold value. These systems may include chillers and heat pump systems, and methods may be applied to chillers or heat pump systems.

A refrigeration cycle apparatus includes a refrigeration circuit in which non-azeotropic refrigerant mixture circulates. The refrigeration circuit includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, an expansion valve, and a four-way valve. The four-way valve is configured to assume a first state and a second state. The outdoor heat exchanger includes a plurality of refrigerant flow paths and a linear flow path switching valve configured to switch connections of the plurality of refrigerant flow paths between a series state in which the non-azeotropic refrigerant mixture flows through the plurality of refrigerant flow paths in series and a parallel state in which the non-azeotropic refrigerant mixture flows through the plurality of refrigerant flow paths in parallel. A controller switches the linear flow path switching valve between the series state and the parallel state when a multi-way valve is in the second state.

In an air conditioner, an inlet pipe penetrates a location that is offset towards an outer circumferential side from an apex portion of a top portion. The suction pipe penetrates a location that is offset towards the outer circumferential side from an apex portion of a bottom portion and is inserted into the interior of the main body portion, and the suction inner pipe, which constitutes a portion of the suction pipe that lies in the interior of the main body portion, extends as far as an upper portion of the main body portion so that an inlet port is disposed in a space defined by the top portion. Then, the suction inner pipe includes a bend portion that is bent from a location lying slightly above a location where the suction pipe penetrates the bottom portion as an originating point.

An air-conditioning apparatus includes a refrigerant circuit, an air-conditioning load state detection unit, an operation-state detection unit, and a controller. The refrigerant circuit includes a main circuit and a bypass circuit. The air-conditioning apparatus has a simultaneous heating and defrosting operation mode. In the simultaneous heating and defrosting operation mode, the controller controls a compressor, a pressure reducing device, and a defrosting refrigerant pressure-reducing device such that control amounts of the compressor, the pressure reducing device, and the defrosting refrigerant pressure-reducing device reach respective normal-time control target values that are set based on an air-conditioning load state and an operation state.

In order to increase the evaporation capacity of a use-side heat exchanger regardless of operating conditions, a suction injection pipe and a subcooling heat exchanger are provided at a main refrigerant circuit in which a 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 controller performs control for switching between a cooling action of the subcooling heat-exchanger that cools the main refrigerant that is sent to a main use-side heat exchanger by using the suction injection pipe and the subcooling heat exchanger, and a cooling action of the sub-refrigerant-circuit that cools the main refrigerant that is sent to the main use-side heat exchanger by using the sub-refrigerant circuit 80.