A refrigerator includes a first refrigeration cycle unit that is configured to circulate a first refrigerant and that includes a first compressor, a first condenser, a first expansion device, and a first evaporator, a second refrigeration cycle unit that is configured to circulate a second refrigerant and that includes a second compressor, a second condenser, a second expansion device, and a second evaporator, a first valve unit installed at an outlet side of the first compressor, and a first hot gas path configured to extend from the first valve unit to the second evaporator and configured to supply the first refrigerant to the second evaporator.

There is provided a vehicle air conditioning apparatus capable of removing frost formed on an outdoor heat exchanger at the same time as cooling of a battery. The vehicle air conditioning apparatus performs the operation in a first battery cooling mode, a second battery cooling mode, or a solo battery cooling mode, when it is determined that the battery needs to be cooled and also determined that the frost formed on the outdoor heat exchanger needs to be removed. By this means, it is possible to cool the battery and melt the frost formed on the outdoor heat exchanger at the same time by the battery cooling operation, and therefore it is possible to reduce the power consumption compared to the case where the battery cooling operation and the defrosting operation are performed individually.

A method of operating an HVAC system using a controller includes predicting a first predicted temperature of an enclosed space during an unoccupied time with the HVAC system off. The controller determines if the first predicted temperature is less than a set-point temperature. Responsive to a determination that the first predicted temperature is less than the set-point temperature, the controller predicts a second predicted temperature of the enclosed space if the HVAC system is operated for a first runtime. The controller determines if the second predicted temperature is less than the set-point temperature and, responsive to a determination that the second predicted temperature is not less than the set-point temperature, the controller operates the HVAC system for the first runtime.

An air conditioner having a freezing function includes an external device, an expansion valve, a condenser, a compressor, and an evaporator. The compressor, the condenser, the expansion valve, the external device, and the evaporator are sequentially connected to form a loop. The external device includes a capillary tube and a cut-off valve. The capillary tube is spirally disposed. The cut-off valve is connected in parallel to the capillary tube. A tube coupling is disposed at each of two ends of the capillary tube. The tube couplings are separately fixedly connected to a conduit extending from the expansion valve and a conduit extending from the evaporator. A spiral capillary tube is connected between an expansion valve and an evaporator in an air conditioner, so that the pressure of a liquid refrigerant is reduced when entering the capillary tube, thereby lowering the lowest refrigeration temperature to implement quick cooling.

An air conditioning apparatus may include an outdoor unit through which a first fluid, such as refrigerant circulates, an indoor unit through which a second fluid, such as water circulates, a heat exchange device which is configured to connect the outdoor unit to the indoor unit and in which the first fluid and the second fluid are heat-exchanged with each other, a first inner tube which is configured to connect the outdoor unit to the heat exchange device and through which the first fluid at high-pressure flows, a second inner tube which is configured to connect the outdoor unit to the heat exchange device and through which the first fluid at low-pressure flows, and a third inner tube which is configured to connect the outdoor unit to the heat exchange device and through which the first fluid in liquid form flows. The heat exchange device may include a bypass tube configured to bypass the second inner tube and a flow control valve provided in the bypass tube.

A heat pump system that can be selectively utilized to discharge excessive heating and cooling capacity toward secondary devices of the system to maintain operation of the heat pump system to better manage the respective temperatures associated with the fluid flows in a manner that reduces the need for cycling the heat pump system ON and OFF to attain desired fluid output temperature manipulations.

Various embodiments of a heat pump system are disclosed to provide improved and flexible heat pump operation when dehumidification of the conditioned space is required. In one embodiment, a heat pump system includes a heat pump loop comprising a refrigerant circuit that fluidly interconnects (1) a compressor; (2) a source heat exchanger; (3) a source heat exchanger bypass circuit comprising a bypass valve; (4) a space heat exchanger; (5) a reversing valve positioned on the discharge side of the compressor; (6) a reheat circuit comprising a reheat heat exchanger; (7) first and second expansion devices; and (8) first and second expansion device bypass circuits configured to allow refrigerant to bypass the first and second expansion devices, respectively, where the first and second bypass circuits include first and second check valves, respectively; and (9) a 3-way valve configured to selectively direct refrigerant flow to the first expansion device, the reheat circuit, and the second expansion device.

In an air-conditioning system including a thermal storage heat exchanger, a refrigerant circuit is configured such that an indoor heat exchanger and a receiver communicate with the thermal storage heat exchanger when an operational mode of the refrigerant circuit is switched to a cooling operation in which the thermal storage heat exchanger serves as a radiator and the indoor heat exchanger serves as an evaporator.

Provided is an air conditioning apparatus. The air conditioning apparatus includes a heat exchanger in which the refrigerant and the water are heat-exchanged with each other, a high-pressure guide tube extending from a high-pressure gas tube of an outdoor unit so as to be connected to one side of the heat exchanger, a low-pressure guide tube extending from a low-pressure gas tube of the outdoor unit so as to be combined with the high-pressure guide tube, a liquid guide tube extending from a liquid tube of the outdoor unit so as to be connected to the other side of the heat exchanger, a bypass tube configured to connect a bypass branch point of the high-pressure gas tube to a bypass combination point of the liquid guide tube to bypass a high-pressure refrigerant existing in the high-pressure tube to the liquid guide tube, and a bypass valve installed in the bypass tube.

The refrigeration cycle device includes a compressor, an outside heat exchanger, a cooling pressure reducing unit, an evaporator, a branch portion, a cool down pressure reducing unit, a temperature adjusting unit, a merging portion, a bypass passage, and a first on-off valve. The temperature adjusting unit includes a temperature adjusting heat exchange unit and adjusts a temperature of a temperature adjustment target object. During a cooling and cool down mode, the outside heat exchanger functions as a radiator, and the evaporator and the temperature adjusting heat exchange unit function as heat absorbers. During a target object warm up mode, the refrigerant discharged from the compressor is guided to the temperature adjusting heat exchange unit via the bypass passage, and the heat of the discharged refrigerant is used as a heat source for heating the temperature adjustment target object.