An air conditioner includes an outdoor unit including a compressor for compressing a refrigerant and an outdoor heat exchanger for exchanging heat between the refrigerant and outside air. A ventilation device is connected to a plurality of refrigerant pipes, and configured to direct outside air into an indoor space, and indoor air to the outside. The ventilation device includes a case, a main heat exchanger, a recovery heat exchanger, and a refrigerant distributor. The refrigerant distributor is configured to direct the refrigerant between the main heat exchanger and the recovery heat exchanger.

An air conditioner includes an outdoor unit including a compressor for compressing a refrigerant and an outdoor heat exchanger for exchanging heat between the refrigerant and outside air. A ventilation device is connected to the outdoor unit through a liquid refrigerant pipe, a high-pressure refrigerant pipe, and a low-pressure refrigerant pipe. The ventilation device supplies the outside air to an indoor space, and discharges indoor air to the outside. The ventilation device includes a case, a main heat exchanger, a recovery heat exchanger, a refrigerant distributor, and a re-heat heat exchanger. A liquid refrigerant pipe valve is disposed in the liquid refrigerant pipe for controlling an amount of refrigerant.

An air conditioner includes an outdoor unit having a compressor and an outdoor heat exchanger. A ventilator connected to the outdoor unit by refrigerant pipes allows outside air to pass through a heat exchanger and flow into an indoor space, and allows indoor air to pass through the heat exchanger and flow to an outdoor space. The ventilator includes a supply passage through which the outside air flows into the indoor space, and a discharge passage through which the indoor air is discharged to the outdoor space. The ventilaro also includes a main heat exchanger in the supply passage and a recovery heat exchanger in the discharge passage. A refrigerant distributor supplies the refrigerant from the outdoor unit to the main heat exachager or the recovery heat exchanger, vice-versa. A reheat exchanger in the supply passage heats the air flowing therethrough.

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.

An air conditioner includes a bypass pipe connecting a first bypass branch of a first connection pipe, through which high-pressure refrigerant flows, with a second bypass branch of a third connection pipe, through which low-pressure refrigerant flows, to allow bypassing of high-pressure refrigerant in the first connection pipe to the third connection pipe, and a bypass valve mounted in the bypass pipe. During a cooling operation of an indoor unit, the bypass valve is opened to allow bypassing of high-pressure refrigerant of the first connection pipe to the third connection pipe.

An air conditioning apparatus is provided that may include an outdoor unit including a compressor and an outdoor heat exchanger and through which a refrigerant is circulated, an indoor unit through which a fluid, such as water is circulated, and at least one heat exchange device including a heat exchanger in which the refrigerant and the fluid are heat-exchanged with each other. The at least one heat exchange device may include a high-pressure guide tube that extends from a high-pressure gas tube of the outdoor unit so as to be connected to a first side of the heat exchanger, a low-pressure guide tube that extends 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 that extends from a liquid tube of the outdoor unit so as to be connected to a second side of the heat exchanger, and a solenoid valve installed in the high-pressure guide tube or the low-pressure guide tube to perform an opening and closing operation so as to allow the refrigerant to flow in a first direction. The high-pressure gas tube and the low-pressure gas tube may be connected to each other by a single gas tube, and when the indoor unit performs a cooling operation or a heating operation, flow of refrigerant in the first direction may be blocked in a state in which power is applied to the solenoid valve.

A heat pump system, comprising a compressor, a first heat exchanger, a second heat exchanger, a third heat exchanger, an intermediate heat exchanger, a first throttling element and a first valve member, wherein the intermediate heat exchanger comprises a first heat exchange portion and second heat exchange portion that may carry out heat exchange; a first port of the first heat exchange portion communicates with an inlet of the compressor; a second port of the first heat exchange portion may communicate with at least one among an outlet of the second heat exchanger and a second port of the third heat exchanger; and a first port of the second heat exchange portion may communicate with a first port of the third heat exchanger.

A flow path switching mechanism (70) includes first to fourth flow paths (71, 72, 73, 74) and opening and closing mechanisms (V1, V2, V3, V4, 75, 76) that can each open and close a corresponding one of the flow paths (71, 72, 73, 74). A first connection point (C1) connecting an inflow portion of the first flow path (71) and an inflow portion of the second flow path (72) is connected to a discharge portion of a compression unit (30). A second connection point (C2) connecting an outflow portion of the first flow path (71) and an inflow portion of the third flow path (73) is connected to a gas-side end of a heat source heat exchanger (22). A third connection point (C3) connecting an outflow portion of the second flow path (72) and an inflow portion of the fourth flow path (74) is connected to a gas-side end of a second utilization heat exchanger (85, 93). A fourth connection point (C4) connecting an outflow portion of the third flow path (73) and an outflow portion of the fourth flow path (74), and a gas-side end of a first utilization heat exchanger (83) are connected to a suction portion of the compression unit (30).

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.

An air-conditioning system includes a refrigerant circuit configured to perform a refrigeration cycle. The refrigerant circuit connects a compressor, a utilization-side heat exchanger that performs air conditioning of an indoor space, and a thermal storage heat exchanger. The air-conditioning system executes a first operation in accordance with a reduction command to reduce commercial power consumption in a whole of the air-conditioning system. The first operation allows the utilization-side heat exchanger to perform air conditioning using the thermal storage heat exchanger as a heat source. The air-conditioning system includes a power reduction section configured to perform a first control in synchronization with timing of a start of the first operation. The first control makes the commercial power consumption in the whole of the air-conditioning system equal to or lower than a first value.