An air conditioner including an outdoor unit, an air conditioning indoor unit, a showcase indoor unit, and a combination unit. The combination unit includes a first gas control unit connected to the air conditioning indoor unit gas pipe, a second gas control unit 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. 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 and the showcase indoor unit can use a single outdoor unit, and heat emitted from the air conditioning indoor unit to a room during a heating operation is used as condensation heat of the showcase indoor unit.

An air conditioner may include a continuous refrigeration apparatus including a first gas control unit connected to a first indoor heat exchanger, a second gas control unit connected to a second indoor heat exchanger, a first pipe connecting a liquid pipe of an outdoor unit and a liquid of an indoor unit, and a second pipe branched from the first pipe and connected to the first and second gas control units. The first gas control unit may include a first-first flow path connecting the first gas control unit to the second pipe; a first-second flow path connected to the first-first flow path, and through which refrigerant discharged from the first indoor heat exchanger flows during a refrigeration operation; and a first-third flow path connected in parallel with the first-second flow path, and guiding refrigerant from the compressor to the first indoor heat exchanger during a defrosting operation.

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.

An air-conditioning apparatus includes outdoor units each including a compressor and outdoor heat exchanger, refrigerant flowing through the outdoor units; an indoor unit including an indoor heat exchanger, a heat medium flowing through the indoor unit; relay devices to which the outdoor units are connected, and to which the indoor unit is connected, each relay device includes a heat medium heat exchanger that exchanges heat between the refrigerant and the heat medium; and a controller. The controller controls action of the outdoor units, the indoor unit, and the relay devices. The controller determines necessity for a defrosting operation; responsive the defrosting operation being necessary, compares an indoor unit total load with an outdoor unit total capacity; and controls an operating frequency of the compressor of an outdoor unit other than the outdoor unit on which the defrosting operation is to be performed to increase the outdoor unit total capacity.

An air-conditioning apparatus includes: a plurality of outdoor units each including a compressor and an outdoor heat exchanger, refrigerant flowing through the plurality of outdoor units; an indoor unit including an indoor heat exchanger, a heat medium flowing through the indoor unit; a plurality of relay devices to which the plurality of outdoor units are connected independently, and to which the indoor unit is connected, each of the plurality of relay devices including a heat medium heat exchanger configured to exchange heat between the refrigerant and the heat medium; and a controller configured to control action of the plurality of outdoor units, the indoor unit, and the plurality of relay devices, wherein the controller includes a defrost determination unit configured to determine necessity for a defrosting operation, a load determination unit configured to compare, in a case where the defrosting operation is necessary, an indoor unit total load with an outdoor unit total capacity, and an equipment control unit configured to control an operating frequency of the compressor of an outdoor unit other than the outdoor unit on which the defrosting operation is to be performed such that the outdoor unit total capacity is increased in a case where the indoor unit total load is greater than the outdoor unit total capacity.

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.

An air conditioner performs a heating operation and a cooling operation with enhanced heat exchange performance and also performs a heating continuous operation, while preventing increases in manufacturing cost and packaging volume. An air conditioner comprises a refrigerant circuit through which refrigerant circulates. A second heat exchanger includes a first refrigerant flow path and a second refrigerant flow path. A first port of the flow path switching device is connected to a discharge portion of a compressor. A second port is connected to a first heat exchanger. A third port is connected to an intake portion of the compressor. A fourth port is connected to a pipe that connects a branch point to the first refrigerant flow path. A fifth port is connected to the second refrigerant flow path. A sixth port is connected to the first refrigerant flow path.

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.