A system for air-conditioning and hot-water supply and configured to selectively perform a cooling operation and heating operation, comprising: an outdoor unit having a compressor , an outdoor heat exchanger , a switching valve , an accumulator and an outdoor fan ; a plurality of 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 plurality of indoor units and including a refrigerant-water heat exchanger ; and a controller configured to monitor a request for hot-water supply from the hot-water supply unit ; wherein the outdoor unit , the indoor units , and the hot-water supply unit are connected by a gas main pipe and a liquid main pipe ; during the heating operation, the outdoor unit forms a refrigerant circuit for heating in which the outdoor heating exchanger , the switching valve , the accumulator , the compressor , and the switching valve are sequentially connected in this order from the liquid main pipe side toward the gas main pipe ; during the cooling operation, the outdoor unit forms a refrigerant circuit for cooling in which the switching valve , the accumulator , the compressor , the switching valve , and the outdoor heating exchanger are sequentially connected in this order from the gas main pipe side toward the liquid main pipe ; and the hot-water supply unit has a function of transferring heating energy or cooling energy from the outdoor unit to water so as to perform the heating operation or the cooling operation thereon; characterised in that the controller is further configured to continue a cooling operation after said request has occurred and until a predetermined condition is satisfied where the request for hot-water supply has occurred during said cooling operation at at least one of the plurality of indoor units , and then to start a heating operation. an outdoor unit having a compressor , an outdoor heat exchanger , a switching valve , an accumulator and an outdoor fan ; a plurality of 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 plurality of indoor units and including a refrigerant-water heat exchanger ; and a controller configured to monitor a request for hot-water supply from the hot-water supply unit ; wherein the outdoor unit , the indoor units , and the hot-water supply unit are connected by a gas main pipe and a liquid main pipe ; during the heating operation, the outdoor unit forms a refrigerant circuit for heating in which the outdoor heating exchanger , the switching valve , the accumulator , the compressor , and the switching valve are sequentially connected in this order from the liquid main pipe side toward the gas main pipe ; during the cooling operation, the outdoor unit forms a refrigerant circuit for cooling in which the switching valve , the accumulator , the compressor , the switching valve , and the outdoor heating exchanger are sequentially connected in this order from the gas main pipe side toward the liquid main pipe ; and the hot-water supply unit has a function of transferring heating energy or cooling energy from the outdoor unit to water so as to perform the heating operation or the cooling operation thereon; characterised in that the controller is further configured to continue a cooling operation after said request has occurred and until a predetermined condition is satisfied where the request for hot-water supply has occurred during said cooling operation at at least one of the plurality of indoor units , and then to start a heating operation. <EOS>