The invention relates to a refrigeration installation (1), to a method for same, and to a refrigeration installation system for controlling the temperature of air, including at least one compressor (3), at least one expansion element (39), and at least one first (5) and a second (7) heat exchanger, each of which can be operated as a condenser or a gas cooler, wherein at least one of the heat exchangers can be operated as an evaporator or at least one additional heat exchanger is provided which can be operated as an evaporator. A refrigerant line is equipped with a first valve (11) downstream of at least one compressor (3) at or downstream of a branch (9) and upstream of or at the condenser or gas cooler inlet (15) of the first heat exchanger (5), and a second valve (19) is arranged at or downstream of the condenser or gas cooler outlet (17) of the first heat exchanger (5) and upstream of or as an expansion element. The refrigeration installation (1) contains at least one valve controller (13) for the first (11) and second valve (19) with at least one first and second possible valve set-up in order to displace the refrigerant, wherein the first valve (11) is open while the second valve (19) is closed at the same time in the first set-up and vice versa in the second set-up. The valve controller (13) comprises an automatic regulator which sets the first valve switch set-up for at least one heat exchanger (5, 7) which is not being used as a with refrigerant flowing through condenser or gas cooler at the moment when a specified refrigerant quantity is exceeded in the refrigerant circuit through which refrigerant is flowing.

A low ambient cooling system for a variable refrigerant flow heat pump includes an outdoor air conditioning unit and an indoor air conditioning unit. The outdoor air conditioning unit includes an outdoor heat exchanger with one or more valves that selectively control refrigerant flow through different sections of condenser coils during a low ambient cooling mode. During the low ambient cooling mode, the condenser coils of the outdoor heat exchanger include an active coil section through which refrigerant flows and an inactive coil section that is closed. An outdoor-coil restrictor plate with holes is attached to the active condenser coil in the outdoor air conditioning unit. The outdoor-coil restrictor plate restricts excessive heat release from the active coil section of the condenser coils in the outdoor heat exchanger during the low ambient cooling mode.

A dehumidifying system and method for reducing humidity in ambient air is disclosed. The system includes a circulation unit, a refrigeration unit, a condensate receptacle for receiving condensate generated by the refrigeration unit, a controller to control both the circulation and refrigeration units, and wherein the controller receives input from one or more ambient sensors configured to sense ambient conditions, and a user interface configured to receive input from a user. The system implements variable speed control within the circulation and/or refrigeration unit to maximize efficiency or capacity under a current threshold, and enables the system to delay the need for defrost cycling during low temperature operation.

A method for controlling a vapour compression system, the vapour compression system including a compressor unit with one or more compressors. At least one of the compressors is connectable to a gaseous outlet of a receiver, and at least one of the compressors is connectable to an outlet of an evaporator. A parameter of the vapour compression system is measured, an enthalpy of refrigerant leaving the heat rejecting heat exchanger being derivable from the measured parameter. A setpoint value for a pressure inside the receiver is calculated, based on the measured parameter, and the compressor unit is operated in accordance with the calculated setpoint value, and in order to obtain a pressure inside the receiver which is equal to the calculated setpoint value. The vapour compression system is operated in an energy efficient manner over a wide range of ambient temperatures.

The present disclosure provides an air conditioner system and a control method for the same. The air conditioner system includes: a refrigeration system. A first port of a second four-way valve is connected to a pipeline between the first four-way valve and the indoor heat exchanger, and a second port of a second four-way valve is connected to a first position in a pipeline between the indoor heat exchanger and the outdoor heat exchanger. A first port of the first passage of an auxiliary heat exchanger is in communication with a fourth port of the second four-way valve, and a second port of the first passage is connected to a second position in a pipeline between the indoor heat exchanger and the outdoor heat exchanger.

An air conditioner includes a refrigeration cycle in which a first compressor and a second compressor are connected in parallel, and the first compressor, the second compressor, a first outdoor heat exchanger, a second outdoor heat exchanger, a first indoor heat exchanger, a second indoor heat exchanger, and expansion valves are connected. When the air conditioning apparatus is operated in a first operation mode in which the second outdoor heat exchanger and the first indoor heat exchanger are operated as condensers and the second indoor heat exchanger is operated as an evaporator, refrigerant discharged from the first compressor flows through the first indoor heat exchanger, the expansion valves, and the second indoor heat exchanger in order while bypassing the first outdoor heat exchanger and the second outdoor heat exchanger.

A supplemental heat-providing system is provided for heating a refrigerant. The system includes an outdoor unit that can act as a heat pump located outside a building and configured to use the refrigerant to condition an indoor space inside the building; a hot water heater located in the building and connected to one or more points of use in the building, the hot water heater being configured to heat water and provide the water to the one or more points of use; a water-refrigerant heat exchanger containing a refrigerant pathway and a water pathway, configured to pass the refrigerant from the outdoor unit through the refrigerant pathway, to pass the water from the hot water heater through the water pathway, and to exchange heat from the water to the refrigerant; and a water pump configured to selectively pump the water from the hot water heater through water pathway.

A heat pump arrangement includes a heat pump device, an evaporator cycle interface for inputting liquid to be cooled into the heat pump device and for outputting cooled liquid out of the heat pump device, a condenser cycle interface for inputting liquid to be heated into the heat pump device and for outputting heated liquid out of the heat pump device, a controllable heat exchanger for controllably coupling the evaporator cycle interface and the condenser cycle interface, and a control for controlling the controllable heat exchanger in dependence on an evaporator cycle temperature in the evaporator cycle interface or a condenser cycle temperature in the condenser cycle interface.

A heat pump system, a defrosting method for the heat pump system, and a controller. The heat pump system includes a heat exchanger assembly for exchanging heat with a fluid medium, the heat exchanger assembly comprised a first heat exchanger and a second heat exchanger arranged in parallel, the second heat exchanger being arranged upstream of the first heat exchanger in the flow direction of the fluid medium, and when the heat pump system is operating in a heating mode and the temperature and/or ambient humidity to which the heat exchanger assembly is currently exposed reach a pre-set value, the second heat exchanger and the first heat exchanger function as a condenser and an evaporator, respectively.

A heat exchanger includes plural tubes, a first tank, and a second tank. Refrigerant flows in order of a first internal passage of the first tank, a first tube, the second tank, a second tube, and a second internal passage of the first tank. A channel forming portion is provided inside the second tank to form a refrigerant channel having a cross-sectional area smaller than that of an internal passage of the second tank in a cross-section orthogonal to a longitudinal direction of the second tank. The refrigerant channel is arranged so that a projection area of the refrigerant channel overlaps the tube when viewed in the longitudinal direction of the second tank.