An air-conditioning apparatus includes a refrigerant circuit including first and second load-side heat exchangers, a first flow switching unit located upstream of the second load-side heat exchanger, and a second flow switching unit located downstream of the second load-side heat exchanger, wherein the first flow switching unit is configured to be switched between a first state in which refrigerant communication between a compressor and the second load-side heat exchanger is blocked and a second state in which the compressor is in refrigerant communication with the first and second load-side heat exchangers, and the second flow switching unit is configured to be switched between a third state in which refrigerant communication between the second load-side heat exchanger and a heat-source-side heat exchanger is blocked and a fourth state in which the first load-side heat exchanger is in refrigerant communication with the second load-side heat exchanger and the heat-source-side heat exchanger.

Provided is a refrigeration cycle apparatus configured to perform a heating operation and a simultaneous heating and hot-water supply operation. The refrigeration cycle apparatus is configured to execute an operation mode circulating refrigerant through, in order, a discharge outlet of a compressor, a first heat exchanger, an expansion device, a second heat exchanger provided to a water tank, and a suction inlet of the compressor, and causing the refrigerant flowing through the second heat exchanger to evaporate by heat generated by a heat source provided to the water tank.

An air conditioner including: an outdoor unit, an air conditioning indoor unit, a showcase indoor unit, and a combination unit, wherein the combination unit includes a first gas control unit which is connected to the air conditioning indoor unit gas pipe, a second gas control unit which is connected to the showcase indoor unit gas pipe, a first pipe which connects the outdoor unit liquid pipe and the indoor unit liquid pipe, and a second pipe which connects the first pipe and the second gas control unit, and the first gas control unit and the second gas control unit are converged to be connected to the outdoor unit gas pipe, so that the air conditioning indoor unit for cooling and heating operation and the showcase indoor unit for refrigeration operation can use a single outdoor unit, and the heat emitted from the air conditioning indoor unit to the room during the heating operation of the air conditioning indoor unit is used as the condensation heat of the showcase indoor unit so as to zero the energy use for heating.

An air conditioner including: a continuous refrigeration apparatus comprising a first gas control unit connected to a first indoor heat exchanger of the plurality of indoor heat exchangers, a second gas control unit connected to a second indoor heat exchanger of the plurality of indoor heat exchangers, a first pipe connecting a liquid pipe of the outdoor unit and a liquid of the indoor unit, and a second pipe which is branched from the first pipe and connected to the first gas control unit and the second gas control unit, wherein the first gas control unit comprises: a first-first flow path connecting the first gas control unit to the second pipe; a first-second flow path which is connected to the first-first flow path, and through which the refrigerant discharged from the first indoor heat exchanger flows during a refrigeration operation of the first indoor heat exchanger; and a first-third flow path which is connected in parallel with the first-second flow path, and guides the refrigerant discharged from the compressor to the first indoor heat exchanger during a defrosting operation of the first indoor heat exchanger, and connects a gas pipe of the outdoor unit and the first indoor 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.

The present disclosure discloses a method and a device for controlling an expansion valve. The method includes: when a first specified number of indoor units are in a non-working state, turning off expansion valves corresponding to all the indoor units in the non-working state; and turning on expansion valves corresponding to a second specified number of indoor units in the non-working state in turn according to a predetermined cycle.

If the refrigerant amount balance control is executed, since degrees of opening of indoor expansion valves are narrowed in indoor units whose refrigerant superheating degrees are smaller than an average refrigerant superheating degree, amounts of refrigerant flowing into the indoor expansion valves are decreased. On the other hand, in the indoor unit where the refrigerant superheating degree is higher than the average refrigerant superheating degree, since refrigerant pressure on a downstream side of the indoor expansion valve is also decreased due to the degrees of opening of the indoor expansion valves being narrowed, the difference in pressure between the upstream side and the downstream side of the indoor expansion valve increases and an amount of refrigerant flowing into the indoor unit is increased. Accordingly, cooling ability of the indoor unit increases.

An air conditioner includes an outdoor unit including a compressor, first and second indoor heat exchangers to receive a refrigerant from the outdoor unit, the second indoor heat exchanger receiving the refrigerant independently of the first indoor heat exchanger, and a fan disposed between the first and second indoor heat exchangers. First and second refrigerant pipes form flow paths between the outdoor unit and the first and second indoor heat exchangers. First and second expansion valves are disposed on the first and second refrigerant pipes. Third and fourth refrigerant pipes form flow paths between the compressor and the first and second indoor heat exchangers. A first opening and closing valve selectively opens and closes a fifth refrigerant pipe to selectively allow refrigerant to flow between the second and third refrigerant pipes. Second and third opening and closing valves selectively open and close the second and third refrigerant pipes.

A system for air-conditioning and hot-water supply is configured to selectively perform a cooling operation and a heating operation. The system includes: an outdoor unit having a compressor and an outdoor heat exchanger; at least one or more indoor units each of which is connected to the outdoor unit and includes an indoor heat exchanger; a hot-water supply unit connected to the outdoor unit so as to be arranged in parallel to the indoor unit and including a refrigerant-water heat exchanger; a controller configured to monitor an occurrence of a request for hot-water supply from the hot-water supply unit during the cooling operation being performed at at least one indoor unit among the at least one or more indoor units, and then to start the heating operation in accordance with the request. The controller is further configured to transmit to each of the at least one or more indoor units, which is turned on for the cooling operation, a fan-stop command to stop a fan arranged at each indoor unit.

An air conditioning system and a method of operating the same to improve system performance is provided. The air conditioning system includes an outdoor heat exchanger, an indoor heat exchanger, and a reheat heat exchanger. A reheat temperature sensor positioned proximate an upstream end of the reheat heat exchanger in a cooling mode for measuring a reheat coil saturation temperature. A controller adjusts at least one operating parameter, such as a compressor or fan speed, in response to the reheat coil saturation temperature and/or one of an outdoor coil vapor temperature, an indoor coil vapor temperature, an outdoor coil saturation temperature, and an indoor coil saturation temperature.